UtI'lIt i a rign dis amln mt II Section 1445 Be ergy 'Act 1954 PR October 1975 The U ICBM Force Current Issues and Future Options C H Builder D C Kephart A Laupa A Report prepared fer UNITED STATES AIR FORCE PROJECT RAND SANTA MONICA 90466 COPY NO NATIONAL SECURITY INFORMATION Unauthorized Disclosure Subject to Criminal Sanctions The research described in this Report was sponsored by the United States Air Force under Contract No F44620-73-C-0011 Monitored by the Directorate of Operational Requirements and Development Plans Deputy Chief of Staff Research and Development Hq USAF Reports of The Rand Corporation do not necessarily reflect the opinions or policies of the sponsors of Rand research October 1975 The U S ICBM Force Current ISsues and Future Options U C H Builder D Kephart A 'Laupa AReport prepared for a 7 UNITED STATES AIR FORCE PROJECT 223% 1 by 151$ 254 dared 122- 22-72 I I 4 I- If Tfor CantractE44'620- 73--C 0011__and 91 x 4- 1 Rand j- AF Security Cl ar'aric Guide for 3 CA90406 I-r g NuclearWeapons USAF May 1973 4 Published by The Rand Corporation UNCLASSIFIED This is a summary perspective of the U48 ICBM force The purpose is to provide decisionmakers at all levels with a short but comprehen sive background appreciation of the key isSues and options that have become associated with land based ICBMs The material should use% fu1 in helping to support a wide range of decisions affecting the 2 future COmposition of the ICBM force While the individual topiCs i are not developed in detail sufficient for specific decision situations they do cover a span of concerns end alternatives going beyond what is usually found in any single report or br iefing on the force Providing a Short yet comprehensive review has enforced some econ omies in the selection of material_ Since the intended readers are likely to have more than a pedestrian knowledge of ICBMs the aim is to remind rather than to educate The tutorials are limited to those issues and optibns that seem to pivot on details not Widely disdusSed in the open iiterat re The discussions do not go very much beyond the U S 183M force even though many of the subjects invite if not demand broader consideration of related topics such as the Soviet ICBM force I alternative strategic forces and national security objectives 'These related topics are omitted unless they seem peculiarly relevant to the i U13 ICBM force It is presumed that the audience is familiar with these broader questions The report was prepared as a task on the continuing Project a 5 study entitled Future Strategic Aerospace Force RequiremEnts UNCLASSIFIED UNCLASSIFIED This report presents a broad review of issues and elternatives Shearing On the future of the'U S ICBM forcer The purpose is to pro- vide a background understanding and a persPective to help support de f cisions on force structUre and deployment The historical evolution current status and ongoing plans for the force are briefly summarizen Iserving as a compact reference soureeIand introduction to the U S I IICBMs Issues assOciated with ICBMs in the public debates are developed frogether with outllnes ofI the principal opposing arguments I Future l options beyond those new programmed for the force are identified- and I dlscussed 1i At the end theI anthers present their own subjective assessment of fthe key issues and options They hold that the unresolved pivotal issue Abearing on the future of the ICEM force is whether or not it will evolve Ito play any uniq e roles in our strategic posture The future does eht Ilook promising if IUBMS are viewed simply es en arm of the Tried--cne of mthree ways of doing the same job The authors believe however that ICBMs could emerge preeminent for spec1a1 roles in let least our areas These include ICBMs fittedI for limited strateg1c operations ICBMS as a CosItu 1effective strategic reserVe ICBMs for counterforce and ICBMs for three 1' 1 equ1valence UNCLASSIFIED UNCLASSIFIED vii - The authors appreciate the contributions of Rand colleagues W 4 jBarbieti C M Grain J L _Foster Gerber V G Jackson F S Nyland V Palmer A I Robinson R D Sha et H Shulman and Taylor who provided helpful inputs comments and advice during the preparation of this report UNCLASSIFIED UNCLASSIFIED 'cotIENIs PREFACE ACKNOWIJEDGPIENTS Vii Section I INTRODUCTION 1 Current ICBM Force 2 Current ICBM Force Evolution 6 Current 6 II CURRENT ISSUES ll Survivabilities ll Prelaunch Survivability 12 Ianlight Survivability 22 Postattack and Enduring Survivabilities '23 Capabilities 25 'Countervalue 27 Counterforce 28 Limited Strategic Operations 31 Other Issues 34 Stability I I I 34 Safety 35 Costs 38 3 ICBM FORCE IMPROVEMENT OPTIONS 40 Survivability Enhancement Options 49 Improved Prelaunch Survivability 41 Postattack and Enduring Survivabilities 4 Capability Improvement Options a 48 Improved Counterforce 48 Limited Strategic Operations 54 New Missile Options 56 New Missile Options for Retrofit '57 Illustrative New Missiles and MIRV Payloads 58 New Supplementary ICBM Basing Options I II 60 Some General Characteristics of ICBM Basing 61 Point Targets 65 Line Iargets 70 Area Target'Systems 72 Summary Observations 7 Iv 79 ll'he Pivotal ISSUE sq A Future Without Much Promise 80 UNCLASSIFIED UNCLASSIFIED Se eral Promising Futures Limited Strategic Operations Assured Reserve Capabilities Counterforce Equivalence The Outlook UNCLASSIFIED 82 82 84 85 87 88 -I 11113913110110 The years just ahead are likely to be crucial in determining the -1ong term future of the U S force The mounting pr ssures for dhanges in the force are numerous diverse and conflicting The de cisions to be faced vary in importance 'scope and complexity but colleoti ely they should have a pervasive impact upon the kind of ICBM fforce that will emerge in the 19805 The purpose of this report is so aoutline a bread context for these impending decisions I The division of -this summary perspective between current issues and future options is an artific1al and not entirely satisfactOIy con-3 iVenience - Obv1ously many 1ssues and opt1ons are as intimately asso Eoiated asva problem and its solution But we Observe more often that a singie Option may address seVeral issues Also we are persuaded w lthat complete discussions of the problems and separate discussions oi 3the potential solutiOns preside a better perspeCtive for judgments reboot their relatise importance While preparing this summary persPeetive the authors have formed gtheir own judgments on the issues that are most important and the opf tions that seem promising we recognize an obligatrion to share these Ejudgments because of what they may reveal about our own biases and of the vantage point We have enjoyed For that reason a final Eseparate s ection is included to present our subjective aesessments of the crucial issuES the responsive options and the outlook for the ICBM force As such these assessments reflect the views and gjudgments of the authors not necessarily those of our readers To provide a basis for discussing the current issues and future options for the_U S ICBM force We must first establish a common per fception of the prese force The remainder of this section is a review of the present ICBM force what it is how it came to be and Where3 present plans will take it This compact recital of facts Shauld serve as a useful refetende guide even for those who are most familiar with _theaU S ICBM'force CURRENT ICBM FORCE U The U S ICBM force consists of 1000 Minuteman and 54 Titan missiles operationally deployed in hardened underground launchers at nine CONUS sites as shown in Fig l with Minuteman command control netting as in Fig 2 The principal features of the force are sum marized in Fig 3 Vehicle characteristics are summarized in Table 1 L57 Titan 2 is deployed in six 9-missile squadrons at three wing locations Each missile is on continuous alert with its own co located maintenance qualified launch crew With a throw-weight cape hility more than 4 times that of Minuteman 3 Titan 2 is readily adaptable to a variety of special tasks including F035 and lofted or depressed flight paths Titan 2 trajectories will reach the PRvaith- out overfly1ng Soviet territory As a MIRV launcher Titan 2 could deliver about five Minuteman 2 warheads 97 Minuteman missiles are deployed in six wings each comprise ing three or four squadrons of 50 missiles Squadrons consist of five flights of ten silos and one two-man launch control facility Each Minuteman launcthontrol facility can initiate launching of any mis-j sile in the squadron The launch control facilities and the silos are separated by 5 to 7 mi at Wing all others % Alternate control of Minuteman launching from airborne stations is provided by ALCC and ABNCP aircraft Fig 2 via PACCS command control i communications linkage About 30 aircraft are involved One third of these are usually on 15 minute ground alert at several interior airbases U Each Minuteman wing is serviced at field level by a strategic missile support base that repairs maintains and replaces RVs guid ance systems ground electronics power mechanical systems transporta tion and handling equipment and For depot level iservice boosters go to Bill AFB Utah guidance assemblies to Newark AFB Ohio and reentry systems to Kelly AFB Texas In 1975 the programmed force stabilizes at 54 Titan 2 450 Minuteman 2 and 550 Minuteman 3 Six of the 450 Minuteman 2 boosters are configured to launCh the 494L Emergency Rocket Communications System 4 tivea nd ai sanctions Handle as Restricted Dat foreign dissemination Section 1445' Thls Page 13 Confldenmal Safeguard Inc 6 25 MSR PAR radars 3'0 Spartan Hi - Wot 70 Sprint 1250 fin-'3 Wing I Maimstrom 150 i - so Min 3 wing v1 x Grand Forks' - irhqy a 150 HM5115mm 350 Hing 4 It RE Warren 200 ms wing Whiteman' 150- a r 4 aw _snw-aoa 7 Titan-2 g ttie Rock Titanr-Z 4 $MH Strategic Missi'i e wi'ng M R Missf1e Site Radars v PAR Perimeter Acquis 1'iion Radar A PACCS Attack Cbmmand Control System ALCC Airborne Launch'Controi Center a SAC ABNCP Airborne Nationai Command Post av HQ I @811 VHF PAS Primary Alert System i SAQ Control Net #872 Survivabie Digital Dafa'Link Net ENC Emergency War Order Net Launch Controi Facility LF Launch Fac ity Other Land line - LCFS ASSL Wing Command - Post LF n r i g 7 - w- Central Airfield Mi Distance to 1 ky Targeta LI 'n A Access Percent i 0055 Hing Na Operational of Date ICEHH 5H5 Sqn Volgo Moscow grow Lat lLong Peking Performance and Payload Date 7 Ellsworth s Dak 4 73 50 ea 2 RV - nk uc 830 1b l - Ballistic coefficient 1 CEP current 2200 ft projected 1800 ft range with Mic-1 10 men 2- 0700 11 mi Weapon Bystem reliability - 87 5000 1600 Silo hardness about 2000 psi LCF hardness AAPE Severe damage 5500 1500 RV radar cross section 0015 to 06 m2 at 4309_yo 153 Eh 4590 511 0 5150 '100 Booster Performance Range Payload 41 mi gm whiteman Mo 50 508 10 4 520 351 50 509 11 10 67 50 510 12 38 7I 93u5 4740 5300 5650 100 Mont 50 l9 5 0 341 so 12 2 5 69nine 35 mi clouds spaced 50 n mi Ix f' 2 MINUTEMAN-3 03 w rI 3042100 3 1mm 01035 Range 0 mi Krrasa 1b Con Chaff A 2 1 - coefficient 2300 fig Clouds 13 5 current 1000 ft projected 600 80 Reopen system reliability - 85 A2 6030 3760 None 5110 hardness about 2000 p01 Severe A3 x 0 5030 5550 5270 LCF hardness - 44P6 damage 02 16 55 5620 None 5 0 50 RV radar cross section - Oo oto 8 m2 03 16 9430 4520 4600 800 9 320 14 at 4300 to 153 and 0 30 as etc 2 75 50 321 15 41 10 104 21 4730 5340 5260 32 91 4 saute Performance 50 400 16 Chart clouds are spaced 1 0 mi apart Payload ax HIRV footprint - 300 900 0 mi mi 1b 50 Post 0005 vehicle burn time - 440 sec f 5000 2150 M5 17 Av 1250 500321 50 1 07 18 47 9l 97 4 1 300 1 350 5090 33- 67 550 199 1' 6000 1860 48 4 19 6500 1760 Joe-mm a-mwamnm 4490 5030 4790 100 Minot N Dak701 12m 50 742 48 4I 10l 3 4320 4870 4980 32 99 CEP BB 67 nergy Ilgn dissemination Section 1440 1 to CI F E Warren Wye 50 319 13 Act 1954 - Grand Forks Davis-Fanthan I Arie I 390 1963 RV Mod 3 500 lb Ballistic coeffic1ent I 600 4300 ft Range Payload 0102 range with Min-6 - 5200 0 mi 0 910 532 Weapon system reliability 3 8 5000 10300 a 4730 5380 5620 100 5110 hardness 4OP6 533 Severe damage 5500 9300 LCF hardness - 44P6 2 5000 8700 RV radar cross section - 1 1 to 2 9 6500 3000 at 4300 to 153 MM and 0-40n aspect 7000 7400 374 Pen-aids 6 midcourse decoys or 8 ter 377 34-9I-92-2 4780 5440 5880 99 minal decoys-spaced 12 0 mi apart 200 mi chaff train 570 571 32 2l-110 9 5250 5870 5508 91 mm Booster Performance McConnell Kan 500 381 1963 6 68 Little Rock Ark 500 308 9 1963 9 aRotating-earth access to Soviet ICBMS IRBMs MREMS bomber bases bomber staging 100 6 75 hoses fighter bases and major-population centera Non-Rotating Earth cSupporting Data for Fiscal Year 1976 Budget Eatimates Department of the Air Force submitted to Congrats January 1975 Secret F ig 3- U MSR Radar PAR Radar 30 Spartan 70 Sprint - Sgt u ICBM VEHICLE CHARACTERISTICS U mo 4 -- Titan 2 10 650le payload 230 at max thrust Stage-l Stage 2 Stage 3 weight 113- 329 187 754 132 Frapellant lb 243 869 57 902 Dead weight lb 11 186- 5 580 Load ratio 956' 912 Mass ratio 3 856 4 568 Burn_time sec 185 6 178 3 Thrust vac lb 474 000 100 000 13p vac sec 283 308 1 42 1 35 5-56 6 16 ' Idea1 Velocity 12 311 15 073 Stage ref area sq ft 78 5 78 5 Nozzle exit area sq ft 20 3 22 4 Minuteman 2 1 300 lb payload Weight 1b 72 281 22 062 5 550 Propellant lb 45 800 13 835 3 660 4 419 2 677 590 Load ratio 912 838 861 Mass ratio 2 730 2 682 2 923 Burn time sad 55 8 60 0 54 5 Thrust vac lb 220 000 66 000 18 500 'Isp vac sec 268 1 286 275 7 Liftoff 3 05 2 99 3 33 Burnout thrust wt 8 31 8 02 9 79 Ideal velocity 8 673 9 089 9 569 Stage-ref area sq_ft 20 6 16 4 11 8 Nazzle exit area Sq ft 11-5 12 6 5 Minuteman 3a lb 75 332 24 144 3 398 Propellant 1b 45 51 13 620 5 614 Dead weight 1b 5 437 2 076 784 Load ratio 894 868 871 mass ratio 2 54 2 305 3 017 Burn time sec 60 2 62 2 50 85 Thrust vac 1b 206 487 62 306 32 900 Isp vac sec 271 7' 283 5 298 Liftoff thrust wt 2 741 2 58 3 92 Burnout thrust wt 6 98 5 95 11 82 Ideal VelocitY 8 183 1 628 10 600 Stage ref area sq ft 23 4 14 8 14 8 Nozzle exit area sq ft 11 5 12 6 10 0 aninuteman 3 Pazload Dry bus 348 Burn time 440 sec Propellant 257 Shroud 200 Isp 282 sec Chaff set 210 Velocity 1 400 3-MIRVS 71 050 Thrust Total 2 065 11 axial 316 in pitch 22 6 lb yaw 22 6 lb roll 18 6 1h 0 CURRENT ICBM FORCE EVOLUTION U The Titan program was initiated in 1955 as an alternate and 'backup to Atlas in view of the risks then associated with its pres-i surized structure and to stimulate performance advances by tolerating Qgreater technical risks The resulting Titan 1 was a true two stageg cryogenic-fueled ICBM with a semi monocoque structure The Titan 2 jinitiated in 1959 and declared operational in 1963 featured all- inertial guidance hypergolic noncryogenic storahle propellants and _launching from the silo Its payload was greatly increased over Atlas 9 and Titan 1 U The'Minuteman program originated in 1958 as a second-generation featuring continuously alert solid fueled missiles in dispersed 'unmanned silos under centralized control The Minuteman missile system -was declared operational in December 1962 Its sobsequent evolution and growth are summarized in Fig 4 and Table 2 I Minuteman evolved as a quick response to the early Soviet ICBM deployments in the late 1950s Action on Minuteman 2 began in i 1961 partly as a response to the Soviet 83 9 ICBM and the Galosh anti ballistic missile ABM developments In addition to the major improve ments summarized in Table 2 Minuteman 2 accommodated a change in fifing doctrine from a single spasm reaponse to multiple war plans and target sets The directives for Minuteman 3 implementation in 1966 were partly motivated by the continuing buildup of the Soviet 103M force and the ABM activities at Leningrad and Sary Shagan The major improvements included a new third stage for increased throw weight and MIRV multi Iple independently targeted reentry vehicle payloads in various RV decoy and chaff combinations PROGRAM $95 The Minuteman program funding from FY 1976 to scheduled come rpletion is for and for procurement The major items are Upgraded silos Nuclear hardening program to increase silo hardness from about 300 psi to about 2000 psi Order of effort Wings 2m5 3 6-l-4 Wings 2 and 5 are completed in- 1975 Wing 4 in 1979 -m n u- - Iosh 1000 3 4 800 i800 Mk-i i No MIN TEMAN 2 600 600 FBRMERLY 59l 55 En erg Act 1954 elgn dissemfnatlun Sectlun 144b This Page is Secr t #00 H00 NUTEMAN 7 MINUTEMAN Calendar year strategic missiTe and reentry systems force mix history U Energy Act 1954 3132 Table 2 MINUTEMAN MAJOR EVOLUTIONARY IMPROVEMENTS U Initial Operational Capability 1962 Range -5500 mi Mk 5 31h5 1 Yiel-Eg 3 w 5000 ft 100 psi silo soft support Self-power endurance 6 hr batteries Single target ICC 1963 Mk llA blast hardened Y1eldLv - a I 300 psi silo A I 2 targets f 103 1965 I New second stage I Range 6700 mi I Mk llB EMF electromagnetic pulse hardened Xeray hardened in 1968 2800 ft initially 2200 ft currently I Mk l'chaff pen aids penetration aids I '51105 300 psi _in1tially at least 1000 psi by 1979 I Hardened support facilities I7 Self-power endurance 9 weeks motor generator I 8 targets ase1ective launch f I All-azimuth launch I Time-onutarget Control 5 1 I 100 war plan Optlons I ALCC Airborne launch control Canter MM-3 106 1970 f I New third stage Mk lZ MIRVs hardened for blast EMF X rays 0 Yieldi 1111 Iprojected for RV I 1400 ft current 600-800 ft projected I Chaff decoys pen-aids 300 psi silos initially all at least 1000 psi by 1977 I 3 sets of 3 targets I Command Data Buffer- complete by 1977 ooeszey _nergy Act _1_95_4 - r -9 '6 Command Data BuffeerCDB f Protides MM93 ret rgeiing ce ae m bility at launch control centers CDB reduces the time needed for an individual target change from 24 hr to 36 min The time to retarget the force is reduced from 45 days to 10 hr The CD3 activity runs concurrently with silo up- -grading The schedule Wing 5 in 1975 'Wing 3 in 1976 Wing 6 and Sqdu2Q Wing l in 1977 3 Silo upgrading and CDB are coMbined in the Force ModernizaT tion Program With included for FY 76 the funding from FY 76 to completion is Minuteman Improved Guidance and MM Performance Measurement Funding is for FY 76 to complet1on for RDT6E 1 and procurement on the missile guidance software -leading to 6 - estimated future CEPS of 600 to -800 ft for An 3661 fn- tidnal in conclu6e a pro6 1 hgram to assess and predict MM guidance performance on opera- _tiona1 test launches Mk lgAxreentry vehicle RV Funding from 76 to completiOH is FY 76 advances the yield of Mk lz fro The M1 12l121 production line will be kept open pending a decision to con - vert more to Deployment of starts in MM-3 With smaller RVs Funding from FY 76 to completion is including in FY 76 The program covers demonstration flight testing of a MIRV assembly with 5 to 7 RVs Candidates for testing include Poseidon Mk 3 150 Trident Mke4 210 lb as- well as ABRES Terminal A Eggder and ABRES High Technology Vehicle both in the 20061b 83 9 for Pose-idon a6d -Trident If Fund1ng is $21centinuing program to de-il terminally guided accurately delivered Maneuvering RV designed as a hedge against possible future 5 soviet Reentry Laniuvisreminent 5 c Funding is $55 1M in FY 76 and $70continuing program of RDT6E on Systems to protect RVS against erosion and deflection due to rain ice and snow during descent through the atmosPhere 35 The Minuteman program coSt eXclusive of operation mainte i nence and military Construction is summarized in the following tablE 62 These items are funded separately frOm Minuteman as a parE of the Advanced Ballistic Reentry Systems ABRES program Ongoing spending rate for ABRES is about per year This Pa onfidential 'e10 ' FY 75 To Prior FY 76 Completion Total 3 464 123 172 23 3 782 MMFB Procurement 6 725 657 418 478 8 278 Total 10 189 780 590 501 12 060 6 800 All missiles 18 860 92 The total missile procurement is 668 including 49 f0 and 170 for operational training and spares The total for LMMF3 is 798 including 44 for and 204 for operational training 5 and spares The average cost per missile is about prof cured and about deployed Planned production of termina es in 1976 but funding is projected to hold the booster production line open pending a decision to convert additional to MM-Bs 4V UNCLASSIFIED Il- II CURRENT ISSUES Some important public arguments about national security and stra tegic nuclear forces currently focus on the U S ICBM force The out comes Should be expected to shape the ICBM force that emerges in the 19805 While the public debate often poses broad questiOHS bDo we need Are answers are being sought by ex% amining specific issues suCh as ICBM force survivability counterfotce capabilities and stability It may be a matter of judgment whether I these individUal isSues will dominate the larger arguments but the collective outcomes of these skirmishes may wel 1 circumscribe the future of the ICBM force Our discuSSion of Current issuEs does net attempt to answer the_ larger questions per se Those answers evolve from summary judgments about the specific issues Both the issues and the judgments may Change with people and time The issues we address here are current undecided issues that we believe to be important as well as contro- versial Past issues resolved by events Such as or ABM de fenses are omitted because their significance is historical and we assume a familiarity with that history For each isSUe we outline the principal arguments on eaCh side 'Where we can discern how well the arguments are joined we offer some Observations that may be absent from the present debates In a few cases we take pains to explain an issue because it is not widely dis cussed in the open literature such as the effects of dust and fratri aide in multiple weapon attacks We divide our review of current issues into three parts The first deals with the several aspects of ICBM survivability the second with the capabilities of ICBMS to exe- cute strategic tasks and the third with the perceived qualities or properties of ICBM forces The survivability of the ICBM force is probably the-most widely 3% expressed concern about its future and the basis for most arguments UNCLASSIFIED UNCLASSIFIED -12 favoring curtailment or rebasing i This concern is focused almost ex _clusively upon its survival in a surprise disarming attack This narrow focus has its origins in the assured destruction calculus wherein forces are tested and compared simply for their cost-effectiveness in countervalue retaliation after absorbing a maximum Soviet surprise attack While survivability in an all-out Soviet attack is a vital concern and a useful comparative test of strategic postures it is by no means a sufficient basis for assessing the survival problems or prospects of the ICBM force The significance and likelihood of less extreme attack threats is now recognized Perhaps even more important estimates of a single force element's survival of an attack -taken outside the context of the total strategic posture--are now less accepted as an overriding criterion of force effectiveness - Following are discussions of the prelaunch in flight and endur- ing postwattack survivabilities for the currently configured U S ICBM force under both the present and potential future Soviet threats The options for improving the survivability of the lCBM force are deferred until Sec Prelaunch Survivability The prelaunch survivability of the ICBM force is Characteristically measured by the estimated vulnerabilities of the silos to Soviet attacks These estimates have been challenged as to the technical feasibility of the postulated attacks because of disagreements over the threat and the parameters that affect and the uncertainties in herent in planning and executing a disarming counterforce attack There is no wide agreement as to the fundamentals of an effective attack on the ICBM force such as weapon selection employment tactics or kill mechanics For example one potentially effective scheme would involve attacks in multiple waves with bomb damage assessment between waves But any confidence in the efficiency of multiple wave attacks is weakened by the prospect of retaliatory ICBM launches subsequent to the first attack wave Attacking the entire U S ICEM force in a single wave has been challenged as not credible because of attack timing or_ coordination requirements imposed by such weapon produced effects as dust and fratricide UNCLASSIFIED quantities possible -compensatory improvements in the threat 1 qualitleS'may leave the general level of uncertainty unchanged E3-g U Apart from the attatk scheme variations in the parameters% used to describe either the counterforce threat or the U S ICBM foroe can produce substantial ifferences in the perceptions of CF threat oredibility The most serious threats to the survivability of ICEMs are derived from projections of tutors Soviet capabilities these pro jections vary widely'beoause of implicit assumptions about Soviet teoh- Enologies policies and even international negotiatiOnSQ Both the Equantities and qualities projected for Soviet strategic weaponry have gheen controverted While the SALT agreements have placed limits on i QQY The ma thematical relationships between the probability of i fsurvival of a hard point target and the yield and delivery accuracy Of Ean attacking weapon are well known The dom1nant variable in View of the uncertainties -is delivery accuracy Figure 5 shows the probability of survival from a single shot of a hard target as a function of for several weapon yields The hardening approximates that ht - m L0 1 weapon yield 0 8 036 0 4 Probability of surviva1 0 refrf 1 0 1000 2000 3000 4000 5000 5000 ft U U F19 5 S1ngle- shot probab1l1ty of survival of a 2000- -ps1 target -14- currently associated with severe damage to upgraded Minuteman silos and the range of weapon yields is representative of what might be carried by current and follow on Soviet ICBMs While the heaviest Soviet ICBMs are estimated to be capable of carrying a single their numbers permitted under the SALT interim agreements are not suf ficient for an attack upon even a third of the 0 5 ICBM force I Current Soviet ICBM accuracies have been variously estimated in the range from 6 000 ft down to 1 500 ft CEPs as low as 600 ft _have been projected for the Soviet ICBMs now being deployed These 'estimates applied to Fig 5 indicate that Soviet CEPS are likely to be much more important than weapon yields in affecting the calculated prelaunch survival of the U38 ICBM force in a one on-one attack 3 U -The assumptions about the vulnerability of the ICEM force 'are probably open to some well justified skepticism particularly as ithey have been used in the simple force survivability calculations The weapon effects the damage mechanisms and the failure modes for 5the current ICBM force basing are not sufficiently well understood or confirmed to have been treated so glibly-by either side of the ICEM vulnerability debate 99 The physical Vulnerability of the ICBM force to nuclear weapons is inherently uncertain because of the complexities of the sys items and phenomena involved While there will probably always remain Isome residual uncertainty in vulnerability estimates it is generally accepted that the silos their contents and the launch control fa cilities are reasonably balanced in their design for survival against direct nuclear attacks With the hardness upgrading of the Minuteman facilities the key vulnerabilities are currently thought to be asso ciated with the missile rattle space and launch alignment not the hardness of the silos themselves Although the vulnerability of the ICBM force could be greater than expected because of some unobserved deficiency or weakness it also could turn out to be less than expected through the cumulative effect of conservative design Unless the 'physical vulnerability of the force has been grossly misjudged the precision of the vulnerability estimates should not drive the pre launch survivability calculations a 1 15 99 Figure 6 Illustrates the probability of Minuteman 3110' isurvival in a weapon attack as a function of for several vul Inerability numbers wh1ch have been associated with the uygraded Minute- tman These vulnerability numbers reflect different estimate_s made at -different timIes and refer to damage- levels from 11ght to severe I It is apparent from Figs 5 and 6 that the Spread in res-alts SCross all iof these'vulnerability estimates ls substantially less than that dueI to 'the uncertainties in Soviet weapon CEPS or yields0 6 Probability of survival 0 2 I 1 I 0 1000 2000 3000 4000 5000 6000 CEP ft 0 1 I U 0f surVivaT Effect of g vulnerah 'rty number estma tes with weapon Iiner 3 MT i U Even if these basic parameters de11very CEP weapon yield and target vulnerabillty could be determined with hi gh Confidence 5the sutviVability by the ICEM force of a Soviet attack involves sev 3 eral additional questions One question is the Soviet-capability to for missiles which fail at launch or during flight The SEER-ET- -15 reprogramming of additional missiles for boost phase unreliabilities is technically feasible given provisions for the detection of boost failures and for rapid retargeting Postboost and terminal unrelia bilities are generally thought not to be reprogrammable The problems of coordinating missiles reprogrammed to compensate for boost failures into a single attack wave are believed to be other than trivial I U Another question is how many weapons might be targeted against each ICBM silo in an attack Until redently typical surviva bility analyses for the U S ICBM force assumed that the number of 3Weapons usable is limited only by Soviet rescurces throw weight and technology multiple vehicles and high yield efficiencies As a con- sequence it was not uncommon for the analyses to assume that the Soviet' Imissiles were highly and that the attack on each U S ICBM silo involved two three or more RVs Such assumptions have now come under criticism as being inconsistent with the limitations of weapon inter actions dust and fratricide in mounting an actual large scale attack upon arrays of hard point targets 59 The importance of the issue is illustrated in Fig 7 For current Soviet CEPs estimated at between 1 500 and 6 000 ft the diff ferences in force survival among one two or three weapons per silo are substantial With the yield and combinations projected for future Soviet ICBMs the differences between one and several weapons per silo could be decisive in a counterforce attack- the difference _between tens or hundreds of surviving silos 53f In sum the prelaunch survivability of the ICBM force as estimated by the classical analyses of a direct counterforce attack upon the silos-His dominated by the assessment of Soviet CEPs The hardness of the U S silos and the yields and numbers of Soviet weapons 'become relatively unimportant if Soviet CEPs eventually come to be assessed in the region of 1 000 ft or less The next most important parameter is the number of RVs that can be effectively used to attack Reprogramming denotes the launch of backup missiles against aimpoints targeted by failed missiles generally requiring a capa bility to rapidly insert target data and compute guidance parameters for the reserve missiles 3 i1 i 1 0 1 1 I I Number of weapons per target 0 6 Probability of survivaT 01000 2000 30007 4000 5000 5000 CEP ft U Fig 7w Probab1'11'ty of survive effect of multiple shots 2000 ps1 barge 3 MT weapos weld 11 Each 5110 The arguments about that number are now focused on the con- 1 straints that may be imposed upon weapon effeCts U Dust an d Frat ricide There is some argument about the tech nical fea51b111ty of attacks upon the ICEM force using large numbers of closely spaced RVs because of dust and fratricide nucleag gweapons' mutual interference effects The question is how many RVs I can be effectiveiy targeted on each ICBM 3110 in a single attack thee iwould be sufficiently compressed in time as to deny any intervening'g 1opportunity to launch the force Assuming no shortage of at tack RVs the answer appears to depend upon the time of arrival window for RVs that will avoid serious mutual interference effects and the means for controlling the attaeking missiles within the time and geoi metrical Constraints imposed 39K The weapon interference effec ts of concern are nuclear rad1atlon where the prompt neutron effects on nuclear materials coul cause weapon failure shOCk Waves _where the blast en wind loads 218 upon the RV could cause impact diapersions or structural failures and dust and debris where erosion of the RV heat shield could also - cause diapersions or structural failure These effects can result from multiple detonatibns at the same or adjacent targets 59f In general weapons aimed at the same target define the min imum weapon spacing and hence a lower bound on the time-of arrival window because of the potential for fratricide due to shock anes or radiation This lower bound on weapon time separation is typically 3 to 5 sec depending upon the RV velocity which in turn depends 3 upon whether the RV has a high or low aerodynamic loading beta The gupper bound on the window is defined by shock waves from weapons at gadjacent targets which could cause dispersions of the incoming RV and 3is about 10 to 18 sec depending upon the spacing between adjacent itargets typically 3 to 5 mi in the Minutemen deployments Even thdugh the time of arrival window thus defined is bounded by short term ef fects radiation and shock waves further windows are believed by some to_be closed by dust clouds and falling debris for as long as 30 to 60 min S y If only one RV is targeted on each silo all adjacent weapdns would have to arrive within a span of 10 to 18 sec to avoid interference effects While this degree of attack control is generally believed to be technically feasible backup reprogramming missiles after boost failures within this time window appears to be a significant challenge To reprogram after late failures in the boost phase the reprogrammed missiles may be launch delayed by as much as six minutes with respect to the programmed attack and this difference would have to be recovered in the flight times of the backup missiles combination of means has been proposed for this control of flight times launching the attack from the longest range sites and reprogramming backup missiles from shorter-range sites and launching the attack on lofted tree jectories and reprogramming backups with depressed trajectories The arguments about these possibilities are not so much about their tech4 nical feasibility as their credibility for an actual attack $93 If two'RVs are targeted at the same silo the weapons would have_to be separated by at least 3 to 5 sec and yet all pairs arriv within the same 10 to 18 sec at all adjacent silos The number of arriving weapons to be coordinated within the narrower time constraints 'haS'doubled and the uncertainties in attack timing and weapon effects stem-Siza are seen as being signifiCant when compared to the iattacker's timing tolerances and risks Hence there remains some argument as to the technical feasibility and credibility of a singles rwave coordinated attack neing two surface bursts on each silo S95 Several alternative -attack schemes have been suggested as a gmeans for avoiding int eraction effects with two RVs targeted on each silo One is to ignore the minimum spacing reQuired between'weapons iand use the second weapon as a simp1e backup should the firSt RV fai - either to arrive or to detonate Sines this approach would compensate lionly for- the weapon ayatem unreliability and not for the random aim iing errors it may not be an efficient use of attack resources- lt could however eliminate many of the Complexities of reprogramming gthe attack and some would argue that the Soviets need not be concerded that the use of their larger throw weight be efficient 4 97 Anather approach would be to minimize the dust and debris by iprogramming the first RV to airburst this would be followed by a ground burst of the second RV The timing window might be widened bi as much as five minutes in the period otherwise considered closed by early dust and debris effects This would require airburst fusing and gprobably some hardening of the RVs against the airburst effebts More- Eover the airburst may not be as effe ctive against the silos as a -ground borst and the fusing might be countermeasured 35 Still other tactics include delayed detonation of the weapons earth penetrating mines that could be simultaneously triggered and offset aimpoints that would separate the arriving weapons in spaCe straddling the target rather than separating their time of arrival at the target These demand sacrifices in RV weight or effectiveness -and they appear to be not so much serious proposals as Speculative Jpossibilities for a resourceful and determined attaCker 1 595 It is now generally accepted that three RVs on the same silo wcannot pass through the 10 to 18 sec time-of- arrival window with any Ac-xedibi enargin for _error and still avoid serious interaction effects 97 The dust and fratricide arguments while focused on weapon interference effects and attack schemes to circumvent those effects may epitomize more basic arguments over the use of simplified force exchange calculations to determine ICBM force survivability Many calculations of the future survivability of the current Minuteman have assumed force wide attacks by multiple RVs on each silo while ignoring specific consideration of timing requirements or weapon interference effects Those calculations have been challenged as erroneous over f simplifications of important realities in actual attack planning exemplified by the dust and fratricide considerations These realities cannot be neglected it is argued because their accommodation will -exact heavy tolls in attack resources or effectiveness neither of which can be wasted for credible first strikes against the U S ICBM force 29 An opposing View is that the simplified'calculations are not necessarily invalid because they lack such detail that there are types of attack that can be adequately represented by the simplified calcula tions Even though weapon interference effects are an important aspect in an actual attack this opposing view does not accept that our iknowledge is sufficient to exclude the possibility of multiple RV Iattacks on our silos $97 In any event these arguments have raised doubts about the nefficacy of highly MlRVed missile attacks upon the U S ICBM force lf single wave attacks of more than one or two RVs per silo are discoun ed because of weapon interference effects then the estimated survival df the ICBM force will be less sensitive to increased and even dore dependent on the delivery accuracy of Soviet RVs 87 Launch on Attack Assessment Even if all of the technical uncertainties attending prelaunch survivability were reSOIVed other inherent uncertainties in military and political planning for large-j scale counterforce attacks are likely to remain an issue In addition to the technical uncertainties the attacker's risks of being preempted or having the ICBM force launched before the attack is completed are unquantifiahle One view is that such risks make a deliberate care fully planned attack incredible an opposing view holds that such risks are irrelevant in classical deterrence calculations which are concerned with possibilities more than probabilities SEER-ET- rx2 rh U The mere possibility of the-U S being launched upon Jconfirmation of a Soviet ICBM attack even_if launch oneattack assess- meat is not explicitly adopted as policy is held by some to pose an rintolerable risk in any Soviet contemplation of an effective surprise -attaCk upon ICBM force Even if the Soviets had high confi dence in the silo kill capabilities of their IGBM force it is arguei I that they could not he sure that their attack would be successful be Ecause the Russi ans would have to consider that'Minuteman might be 1 Elaunched aga1nst Russ ian targets in the 30-min warning time be tween the e launch of the Russian ICBMs and their arrival at the Minuteman 31los U There are tWo important aspects to the credibility of this Spotential capability as a eterrent to the Soviets One is how the iSoviets might judge prospective U S actions in the light of our policy statements The President has rejected sole reliance on a 'launch- ion-warning' strategy because it would force us to live at the edge of a precipice and deny us the flexibility we wish to preserve 'WhetEer ithe Soviets might interpret -such policy statements as defining our in tentions or not is unclear and can be argued either Way 3 L87 The other aspect is whether the current n 5 ICBM force-coild 5in fact be launched on attack assessment There is little th t therICBM force can be postured to launch upon almost any arbitrarily small time o-f nOtiCe But tha t is not the same as saying that the qurre-nt capabilities for attack assessment launch procedures command Econtrol and communication 03 links wincluding the national command fauthori-ty- are all routineZy compatible with launChing the force outs Tfrom under an incoming attack If there are weaknesses in our present capabilities they may be known to the Soviets who consequently may gnot be deterred If in a crisis we could pose a credible threat of flaunching ICBMs immediately upon warning then the classical scenario of a carefully aprong Soviet attack would be invalid But to ready all and keep them ready indefinitely has been contested as inconsistent iwith national policyw WW hm d Barry Carter Nuclear Strategy and Nuclear Weapons Scien- tifie American Vol 230 No 5 May 1974 Richard Nixon S Foreign Policy for the Emerg- ing Structure of Peace A Report to the February 9 1972 -22- car If launching the Uls ICBM force upon assessment of a Soviet ICBM attack is accepted as being credible to the Soviets the conceptual possibilities for an effective surprise attack are not exhausted Soviet SLBM attacks upon the U S ICBM force would severely compress - if not deny the time for attack assessment and launching of the force but the hard target kill capabilities of the Soviet SLBM force are not perceived to be adequate for an effective silo attack in the foreseeable future u A more imaginative use of the Soviet SLBM force against ICBMS 'Would be to maintain axe-atmospheric nuclear bursts over U S ICBM asites temporarily until the arrival of the silo-killer ICBMs Thisg pindown scheme would be designed to expose the U S ICBM force 5to ineflight attack if it were launched before the arrival of In-Flight Survivability - U In the absence of significant ABM deployments there are few concerns about the in flight survivability of ICBMS The most frequently discussed involve the following possibilities I interactions with defenses 2 pindown attacks 3 exotic ABM concepts 4 j iinteraction of RVs with extreme but natural environmental conditions and 5 fratricide by earlier arrived weapons The first of these the interaction between U S ICBMs and ABM defenses SAFEGUARD or site de- ifense would be of concern only if U S ABM deployments were greatly iexpanded The current directions in arms control negotiations are lead ing instead toward more stringent limitations on ABM deployment U The Soviet SLBM submarine-launched ballistic missile force is large enough to raise the possibility that might be detonated at high altitude over ICBM launch areas to subject the ICBMS to boost phase damage It has been observed that the ICBMs are relatively vul- inerable while boosting and and that SLBM launchers could be located in advantageous positions to attempt the attack The credi i jbility of this tactic has been challenged on the grounds that the tim ing and execution are both teChnically and Operationally difficult and that it would require committing too many and nuclear powered ballisticemissile submarines in a venture of great risk and un- certainty _How seriously the pindown_threat might be viewed in the e23 m 1N w a future is problematical Improvements in the qualities and numbers of suggest the threat could be worse But ASW surveillance im provements in ICBM hardness better attack assessment sensors to find - safe launch windows and the possibility of nem hasing modes for fall suggest that pindown attacks will not be a serious g r Concerns are Sometimes eXpreSSed about the vulnerability of Cballistic missiles to longerange lasers or electron beam weapons 5 fWhile numerous conoepts for these exotic weapons or their employment have been studied so far they are thought to he either technically iinfeasible or too costly The potential laser threat has resulted in nun-r modest programs t-o balance better the harden1ng of the m13511es The' threat of exot1c weapons is not unique to ICBMs and has not figur ed importantly in any of the recent debates over the U ICBM force 1 $33 Abnormal environmental conditions tan produce water ice and 'dust in the atmosPhere that could accelerate the eroSion of the RVs to 'Lthe point of introduc ing large_ dispersions or even destroying them iThe problem is most severe for RVs having a high aerodynamic loadingg ane concern is that large geographical areas containing targets may be temporarily prot_ected by passing storm systems that interfere with reentry The resolution of the present uncertainties will depend upon current efforts to assess weather in the target areas and to ensure ithat RVs will withstand adverse weather conditions 59 The environmental hazardS-for RVs caused by the detonation of weapons upon closely spaced targets are more severe than those exf a pected from natural phenomena As was deacribed earlier the dust and Efratricide effects can be mitigated'by careful control of the attack itiming at least for one and perhaps two weapons per aim point EPostattack and Enduring Survivabilities s U The importance of long-term or enduring survivability for postattack'w1thhold1ng of the ICEM forcew-or any of the strategic nu gclear forces is not Universally accepted One viewpoint is that the survivability and availability of the ICBM force for more than a few hours after any major attack upon the U S is irrelevant because fthe ICBM force would he launched Within that time period and SEER-ET- zit would be other more important concerns for national survival in that event The opposite viewpoint is that the enduring survivability and availability of the ICBM force is more important than the initial sur Vival in an attack because of the way nuclear conflicts are likely to develop and the political significance of being able to withj 'hold and retain viable strategic forces in a postattack environment 55' The immediate postattack availability of undamaged elements iof the U S ICBM force does not appear to be at issue The force routinely operates on commercial power with diesel electric generators providing primary backup Temporary emergency power is available from 3batteries The batteries are located within the missile silos and are adequate for missile launch operations if executed within a few hours lafter the loss of commercial power or diesel electric backup The I upgrading of the Minuteman silos increases the battery capacity from 6 to 20 hr 98 For longer periods the launch availability of the ICBM force 'in a severely degraded postattack environment is problematical First _there is some uncertainty as to the survivability of the backup diesel- electric generators For the Titan -these generators are within the 'silos but fuel for much more than three days is not For the Minute- man the generators are all outside the silos variously protected they are underground but soft for Wings 1 and II hardened to 25 psi for Wings 111 IV and V and to 300 psi for Wing VI 59f Second there have been reliability problems both in starting the backup generators and in switching from generator to battery power In Spite of the good reputation of diesel-electric equipment for high _reliability this has been one of the most troublesome in the Minuteman system 985 Third there is some concern about the ability to carry out essential maintenance activities in severe postattack environments I While noncritical maintenance is indicated and performed frequently y critical maintenance to restore the launch capability of a Minuteman silo is required 0n the average about once every 6 or 7 weeks Most of the critical maintenance for Minuteman is in other than 'guidance the mean time between failures MTBF for guidance systems is on the order of 5 to 6 months ViSra $96 The direct effects of a large scale attack are likely to 1 include the destruction or damage- of substan tia1 quantit ies of maintee i nance resources and the indirect effects fallout and transpor- tation damage might delay access to the silos The tunnel the Titan silos from the launch control facility overcomes part of the Lproblem as long as the required maintenance tasks are within the ref sources of the launch crew T ie extent of these concerns for the enduring aeailabilityi 10f the ICEM force is illustrated by the following exemplary calculawi Igtion An attack by 1 000 reliable each having a yield of 1 2 MT end a CEP of 3 500 ft upon the Minutemen force is estimated to leave abOut 840 silos surviving 0n battery power these 840 remaini operable for less than a day The Same attack is estimated to destroy Eall but about 165 dieSe1 e1ectric generators as a coZZateraZ e fect j If 75 percent of the Surviving generators are successfully started and switched over to supply power abOUt 125 silos would remain operable after the first day following the attack If the for critical fmaintenanCe is taken at 40 days the number of alert missiles would 'idrop below 100 within ten days and below 60 within a month While 3 the numbers are arguable the calculation does indicate that attacks Eincapable of destroying more than a modest fraction of the ICEM force might severely jeopardize the enduring availability of the force U Finally the enduring survivability of the ICEM force could gbe circumscribed by the Vulnerability of the current basing structure gto follow up bomber attacks Since bomber attacks would require hours to execute- and probably would be preceded by considerable warning- I ithis threat is viewed as being princ ipally against withheld ICBMs and ihence a concern for their end uring survival The credibility of Such follow up bomber attacks on the ICEM force is seen by some as being enhanced by the paucity of air defenses to protect the U ICEM 'force and the potential efficiency of bomber attacks in the absence Qof opposing air defenses U A demurring view is that air defenses to preclude bomber ettaCks on withheld still have some advantage today But if the Soviets deploy their nemeIRVed IGBMs up re the limits This Page is Unclassified 26 allowed by the Interim the USSR would have enough RVs to launch a series of follow up attacks against our withheld Thus we would need a balanced defense against both missiles and bombers Such a defense is foreclosed by the ABM Treaty CAPABILITIES The capabilities of the ICBM force have been issues in several important arguments Some of these arguments while apparently centered gon the ICBM really reflect some basic differences in perceptions of the purposes and uses of strategic fOICes The answers to the central 1 I questions of What we want of our strategic posture and what we expect our strategic forces to be capable of doing under various circumstandes are of course vital to any assessment of the capabilities and qual _ities of the ICBM force But this is not the place to elaborate upon Ithe broader questions of strategic posture planning objectives or 1 criteria they are worthy of separate attention In past public discussions the capabilities of our strategic offensiye forces have been typically appraised quite narrowly as apf plied just to countervalue tasks assured destruction such an l-appraisal generates a simple criterion for comparing the relative cost and effectiveness of competing force elements While other tasks Iespecially counterforce tasks have long been recognized within the - military planning community they are not yet widely accepted in public discussions as a basis for strategic force planning It is apparent that the new directions for U S strategic nuclear policy as proposed rby the Secretary of Defense are toward a broader interpretation of the strategic tasks to be considered Thus even in the public discussions the capabilities of strategic forces may be appraised more broadly than they have been to include counterforce tasks and limited strategic I Operations tasks still to be fully defined or widely embraced But even within this breadened interpretatiOn of the strategic tasks there remains the important question of Whether the ICBM a Quotations from the Report of the Secretary of Defense James R Schlesinger to the Congress on the FY 1975 Defense Budget and FY 197541979 Defense Program dated March r 1974 WT- UNCLASSIFIED 727 One of the three strategic offensive force elements that compo-5e the Triad- enjoys a unique role in the strategic posture The answer depends upon the scope of the synergism ascribed to the Triad while the elements of the Triad are recognized as being mutually sup port ive in their survivability a gainst attack are they also to be i mutually supportive in their diverse capabilities to execute s-trategic tasks Here it is sufficient to refer to three broad strategic tasks 3 1 that encompass those objectives and roles most frequently cited we a shall deliberately not develop the major arguments that support the i contributions of these strategic tasks to national security or their 3 implications for the strategic posture- The three strategic tasks are l Countervalue CV major strikes against a broad spectrum of civil and military targets 2 Counterforce CF Major strikes against selected strategic force targets - 3 Limited strategic operations L503 High confidence limited and closely controlled strikes against selected civil or military targets Countervalue A 'Excepting their survivability the capabilities of ICBMs for countervalue tasks are generally admitted In the absence of major ABM deployments- as presently prescribed by agreements there is virtually no doubt that ICBMs can eXecute countervalue strikes a provided enough survive until a decision is made to launch them In r-such characteristics as weapon yields accuracy respOnse times posi- rive control and reliability the capabilities of ICBMs are generally more than adeQuate for the modest teChnical demands of countervalue tasks Survivability has been addressed from at least three directions One is to forget about it by releasing the our planning from any major contribution to counteIValue tasksi Another is to seek the means for improving the survivability of the ICBMS as by rebasing the force And a third approach iS'tO consider how a small number of UNCLASSIFIED UNCLASSIFIED surviving ICBMs might be made more effective for countervalue tasks via such improvements as increasing the throw weight and number of RVs per missile Counterforce The counterforce capability of the U S ICBM force is one of the most controversial issues in national security policy and planning today Because counterforce is almost always considered in the con- text of a classical missile duel in which the ICBM forces of the two Opponents are pitted against eath other in an isolated series of ex changes counterforce tasks have devolved to silo busting hence the counterforce capabilities of ICBMS have become synOnymous with hard target kill capabilities and in the words of the Secretary of Defense Any discussion of hardwtarget kill capability inevitably arouses In a broader sense if counterforce tasks are taken to include strikes against the full array of strategiceforce-related targets encompassing airbases submarine ports C3 and defense sites then the counterforce potentials of ICBMs include much more than hard target kill capability Against many of these relatively soft targets the yield and the accuracy of U S ICBMs are more than adequate Against some such as the submarines in port or the C3 and defense sites the i short delivery times of ICBMs preclude protective reactions Thus the counterforce capabilities of the U S ICBM force for quick and confi- dent delivery of nuclear weapons are significant quite apart from the ability to kill hard targets Nevertheless the public discussion of counterforce is likely to remain more narrowly oriented within the context of missile exchanges The SALT agreements have the effect of inviting comparison of similar forces and silo-based ICBMs are unique among strategic furces in that they are the principal threat to their counterparts Thus the counter- force capabilities of the U S ICEM force are certain to be compared with the Soviet ICBM force both in fact and in appearance 7 Report of Secretary of Defense James R Schlesinger to the Con grass on the FY 1976 and Transition Budgets FY 1977 Authorization Request and FY 1976 1980 Defense Programs February 5 1975 UNCLASSIFIED Unauthorized sublect to admini'stra-I ve and crimln ctlons Handle as Restricted 5 a $2321 U The feptual aspects of concern are the relative survivabil 1t ies and hard-target ki11 capabilities oi the ICBM'forees _ The hard-target kill capabilities 9f the current ICBM force are A medest we could not expect te kill even one Soviet silo for each S 'reliable missile firedm As in Table 3 for reptEsEntatiVe hard ened targets the accuracy and weapon yield c 0mbinations for eurxent ICBMs do not provide high damage probabilities unless mu1tip1e RVs are i employed against each target However see above under Dust and Fretricide The current Soviet ICUM force has the same problem despite signi icant differehces in the two forces Table 3 DAMAGE PROBABILITIES FOR RELIA-BLE ICBMs AGAINST REPRESENTATIVE TARGETS U- Minuteman 2 Minutemen 31- Titan 2 Target 3 _11_Sh r Vulnerability lm z ag y Number a 2290 ft 1000 ft '4300 33132 58 i 65 1 RV 58 Some weepdn 88 2 storage sites 96 3 37% 49 55 55 5319 silos 80 191 481316 16 18 a 182 New 1013M silos 33 146 51P6 11 12 13 Some weapon i 22 storage sites 32 and control centers U The technical feasibility bf dev loping herd target kill capabilities in ICBMS has never been seriously questioned since their first operational deployments While there may be some COnfusion about har target kill capabilities in 3 5 and the Energy Act 1954 This Page is Unclassified c 1301 central issue is the fhture development of these capabilities es pec- 7w ially by the United States It is apparent that the controversy surf rounding the need for hard-target kill capabilities is durable and its resolution is not in sight The future problem is another contingency about which we must remain concerned Since both we and the Soviet Union are investing so much of our capability for flexible and controlled responses in our ICBM forces these forces could become tempting targets assuming that one or both sides acquire much more substantial hard target kill capa bilities than they currently possess If one side could remove the 3 other' 3 Capability for flexible and controlled responses he might find ways of exercising coercion and extracting concessions without triggering the final holocaust Even if this future problem should not materialize in fact it is currently arising in appearances- as the opposing ICBM forces are compared on measures that are easily-or widely appreciated numbers of missiles throw weights and the numbers of RVs per missile It is I on these measures and not on the more esoteric and relevant to counter force parameters that much of the public and political comparison is made Under the terms of the Vladivostok Agreement and given the aSym metries between the U S and Soviet predilections in strategic force postures one would not expect the two opposing ICBM forces to compare closely in appearance But the problem is not one of small differences it is that the throw weight of the Soviet ICBMs will centinue to ex- ceed that of the U S Minuteman force by a very substantial amount tperhaps by as much as a factor of six unless the United States also increases its ICEM The significance of this large disparity in appearances is not clear but permitting it to remain un- challenged has been opposed on the principles of essentia l equivalence as perceived by both superpower and nonsuperpower nations The principal dissenting View is that matching the Soviets by de- velOping counterforce capabilities hard target kill capabilities 7E nihi w 4- leads to undes1rable instabllities in which each side perceives an advantage 1n attaeking first The root cause of the COncern is seen-gi as the vulnerabilities of present landebased ICBMs to their opposing cbunterparts It is argued that if vulnerabilities are removed by 4 reb asing the ICEM force or by eliminating 1t then the development of hardwtarget kill capabilities will be of no particular signif1- canoe As to the capability for flexible and controlled rasponses new a being invested in our ICBM forces it is held to be either unnecessary or better invested in more survivable forces U In sum present counterforce capabilities of the S '_ force may be significant or- marginaL depending on how broadly or narrowly one defines the counterforce task The attainment of a j counterforce hard-target kill capability 1s technically feasible and git goes to the Very heart of U S strate gic nuclear policy What dog we eXpect of strategic offensive forces and what kind of posture are Ewe trying to maintain AlthOugh neither a consensus not unequivocale answers are likely to be forthcoming a resolution of the cOunterfor e 2 issue would seem to demand nothing less than both i Limited Strategis Operations U The Seeretary of De fense ha s stated that as nat1onal policy -we shall continue to acquire and be prepared to implement a number of 3more limited response options Such options would provide the Pre31e dent with flexibility in contingencies less than a general nuclear war would provide a series of- measured responses to aggression which have- some relation to the provocation have prospects of terminating host1l ities before general nuclear war breaks out and leave Some possibility 3 for restoring det rrence Our objective remains deterrence but modern deterrence across the spectrum of nu c1ear threat 597' Now generally called Limited Strategic Operations L303 the czoncept involves the controlled use or the threat of use of limited 1 numbers of strategic nuclear weapons against selected civil or military targetsa The context is rather ill de 1ned at this time - U Ibid 32s Some View LSOs as political coercive events designed to alter the tar - get nation's crisis situation assessment and decision processes others see it as escalation in an ongoing conventional conflict possibly lead- ing to general nuclear war Many agree however that while preplanning is important no amount of preplanning will be able to eliminate sure prises if a limited strategic conflict Occurs The essential factors - in coping with surprises are believed to lie in the flexibility of national security institutions and in the variety of weapon capabilities U Among the potential advantages of ICBMs for LSOs are positive 5 CB quick response flexible targeting high confidence penetration and acturacy These features are generally accepted both as applicable to the ICBM force and as desirable for LSO planning But they are not exclusive With the ICEM force Consider C3 for example Only if Soviet strikes escalate to a level outside the intended scope of LSOs or if they are selectively attacked are CONUS 83 facilities likely to be disrupted It follows that in the conditions and circumstances usually aesociated with LSOS secure 03 will be available to all of our strategic forces U In assessing the attractiveness of ICBMs over for LSQs the case may rest on other than the widely appreciated differences in delivery accuracy or assured two-way command communication fIt is not lprimarily A submarine like the Poseidon is hard to adapt to because you have so many MIRVs permissible and so many misf siles per boat As soon as you fire you expose the boat Consequently the ICBM is a far more useful instrument for this kind of strategy than is the SL3 U It is not evident that the targeting flexibility or accuracy of the ICBM force is superior to that of the strategic bomber force or that the penetration capabilities of the ICBM are better than those of the SLBM Although the aggregate- may fulfill the requiref ments of LSOs better than bombers or neither has this been demonstrated nor its importance established a U Statement by Secretary of Defense James R Schlesinger inia hearing before the Subcommittee on Arms Control International Law and rganization of the Senate Cemmittee on'Foreign Relations March 1974 a 1 as 130 assesses 51 team taste e913 gfound in the prosp ects for destroying hardened targets and limiting unwanted collateral damage While the targets seleCted for L305 mayT differ depending on the initiating scenario and the intent commnni cated they may include targets -from-soft to supethatd But as-shown in Table 3 the hard-target kill capabilities of the current ICBMs gate marginal unless multiple RVs are allocated to each target Apart iftom the cited difficulties in targeting multiple Rvs-against a single point target it is also conceivable that more than one'Weapoh per t_arget scold be undesirable in those circumstances where the numbers lof nuclear weapons employed per as have significance as signals of fintent ' U This alSo raises the question of whether the multiple weapons got the Minutemen 3 may be less selectively employable than the single jweapon of the Minutemen 2 If Collateral damage considerations cyst ride the lesset yields and the higher accuracy of the Minuteman 3 age pteferable although its multiple RVs might not be desired i U The suitability of for LSOs ha-s also been questioned on the effect of their first use While the strategic jbomber fore-e has been employed in limited conflicts with conventional iiweaponry ballistic missiles have never been associated with anything iother than general nuclear war The introduction of ICBMS into a con- Tflict at a stage where escalation control is the paramount concern Ecould be viewed asva preterious step On the other hand one objective Lof LSOs involves the notion of conveying coercive Signals of resolve lthese signalling objectives idire warning and deep alarm and the nee of ICBMs could contribute to 1 91 In sum the L30 capabilities of the ICEM forte may be more 'vcgidely accepted in general than they are demonstrable in specifics f jat leaSt in comparison with our other st rategic oftensive forces In the political and military contexts generally applied to LSOs it is fact clearly evident that the capabilities-of the ICEM force in any single aspect are unique The relatiVe attraotiveness of ICBMs over other strategic offensive force elements for LSOS probably lies in Etheir potential for extremely high accoracy and high confidence delivery coupled with unquestioned uif not singular capabilities for quick response flexible targeting and positive 03 OTHER ISSUES U There are several other important issues which seem to arise indirectly from perceptions of the survivabilities and capabilities of the ICBM force Three of these issues are Sufficiently controversial 5 and durable to warrant discussion here They are the stability safety and cost of the U S ICBM force Stability U It is widely held that opposing ICBM forces if mutually capable or threatening the survival of their counterparts are unstable forces One form of instability is perceived to lie in the incentives for each side to attack preemptively in a crisis crisis instability - that is to use its ICBMs before losing them in an opponent's attack Sudh an instability is seen to be aggravated by increasing the kill capabilities or the vulnerabilities of the ICEM forces on either side rSince increasing vulnerabilities are not actively sought but followf from an opponent's increased kill capabilities concerns for the Estability of opposed ICBM forces are most evident in discussions of potential improvements in ICBM capabilities to kill hard targets U The charge that opposing ICBM forces may be unstable by in- viting preemptive attacks in a crisis has evoked several counterargum ments One of the simplest is that ICBM forces do not possess the 5capabilities for confident disarming attacks against their counter parts Another is that a successful disarming attack against ICBMs is insufficient in a world that also contains and bombers es E pecially if that attack is an aWesome provocation because of the necessarily large amounts of force expended Still another counter argument is that such attacks would not be contemplated because of the risk that the threatened ICBMs would be launched out from under the iimpending attack U The implications of these opposing arguments are not likely _to omfort anyone'but their proponents One View supports the uni lateral abandonment of hardmtarget kill capabilities or even of the UNCLASSIFIED 35s entire 103M force The other View suggests that there need to worry because the attacks will not really Work and therefore will not be attempted Unfortunately the issue is also beclou ed-when other bIoader interpretations of stability are invdked especially those of arms race stability It has been theorized that Opposing ICBM forces may stimulate -Spiraling increases in the ICEM force levels- an arms race instability eSuch an instability is theoretically aggravated by increasing the kill capabilities or the levels of surviVal required of the ICBM forces on either side Further if the leVel and capabilities of the survivors are required to be-Sufficient to restore a balance between the opposing ICBM forces stable force levels are theoretically unobtainable At least one of the objectives of SALT is to halt spiraling force levels While such theoretical cansideratiOns provide a logical-basis for speculating On the role of 103M fbrces in the dynamics of arms races they do not appear to-be supported by serious historical research Other factors politica1 institutional and ecdnomice-seem to be more important determinants of ICBM force levels than do the abstract cri' i teria of strategic theory and calculus In sum the stability of ICBM forces is an isSue that is not 3 Sharply focused in large part because the concept of stability is it self subject to arguments over its definition or relevance What can be said with some confidence is that there is much wider aCcord about i the assumption that ICBM forces are unstable than there is about the definition context or significance of instability That assumption is likely to persist as long as the indictment of ICBM force instav bility rests on simple or naive logic while its refutation continues 3 to depend upon more complex or esoteric cOnsiderations - Safety The presence of the ICBM force in CONUS as it_may affect nuclear deterrence and public safety is an explicit issue in some of the argu- jments over land versus sea basing for the missiles The presence of the force in CONUS can alternatively'be viewed as an undesirable invie tation to nuclear attacks upon our-homeland or as an awesome and de 7 Sirable deterrent to opportunistic upon our strategic forces UNCLASSIFIED NH may be the most desirable attribute of land-based systems UNCLASSIFIED r36 One view is that the very existence of has made the land mass of each superpower an irresistible magnet for the strategic offen- sive force of the other Thus the ICBMS by their very presence in the heart of North America are endangering the people they are supposed to protect This view has been expressed in advocating the sea basing of strategic forces as a direction for SALT negotiations The opposite view has been taken on the basis of the philosophy of deterrence Our land based systems may be thought of as assuring a determined reaponse by requiring a nuclear attack on U S territory if they are to be disarmed By some calculations of deterrence this hi Un- - pleasant as it may be it appears that the risk of causing collateral fatalities is a positive deterrent to Soviet firs strike counterforce attacks and is an element in our deterrent posture The argument then pivots on which risk should be of greater con cern the risk of collateral damage if deterrence fails or the risk that deterrence might fail in the absence of collateral damage pros pects While both risks may be appreciated as valid concerns for national safety and security they are fundamentally different in focus and philosophy One is a concern for the consequences of cons flict while the other is a concern for the occurrence of conflict From either point of View the amount of collateral damage that i might be caused by an attack upon the current ICBM force especially as compared to attacks upon other strategic force elements- is pertie nent Damage estimates particularly predictions of fatalities due to fallout are notoriously uncertain but the results of some repre- sentative calculations may be cited to indicate the general levels of eXpected damage The Vulnerable Homelands by Commander Paul H Backus USN v 3 Naval Institute PROCEEDINGS Vol 96 No 12 814 Decem ber 1970 The Only OptiOn by George E Lowe 0 5 Naval Institute PRO- CEEDINGS Vol 97 No 4 818 April 1971 $Comment and Discussion by Robert I Widder U S Naval Insti- tute PROCEEDINGS Vol 98 No 4 830 April 1972 as Comment and Discussion by Dr Russel D Shaver U S Naval Insti- tute PROCEEDINGS Vol No 11 825 November 1971 UNCLASSIFIED c3lzo 525 For attacks open hardened Silo-based ICBM forces the prin i cipal potential for collateral damage is from fallout casualties due to prompt weapon effects are negligible by-comparison One estimate - of the fallout fatalities from an attack with One surface burst 5-HT 2 weapon upon each of l 223 sites associated with the U S IGBM ferce 3 is about 13 percent of the U15 population assuming negligible shelter 3 - a i pretection The estimation entertainties are illustrated by another I calculation for a similar attackn but using a different analytical in 11 man modelTe which puts the fallo ut casualties at between two and fourteen percent depending upon wind variations One important dimension in these estimates is the Weight of the attack another is the intent of the attacker whether or not he itakes pains in minimize collateral damage Still another dimension i is the degree of fallout protection assdmed For example an attack with weapons detonated at or near optimUm height of burst upon the bulk of the ICBM force- the 850 Minuteman missiles in the 3 remote northern BONUS in fatalities as low as 0 15 w v percent of the UQS population assuming maximum utilization of exist ing civil defense facilities 595 This wide-range of estimates -vary1ng by a factor of almost 100 within plausible sets of assumptions probably has significance 3 only when cempared with est_imates of collateral damage for attacks on gthe other'strategic offensive force elements For attacks on the sine- tegic bomber force the principal potential for collateral damage is 1 2 the casualties due to prompt effects An attack with a single air 'burst leMT weapon over each of air bases has been estimated td _NncZear Vulnerability Analysis Damage Assessment Handbook U Vbl National Military Command System Support Center 331 December _l970 Secret L H Wagner Quick count A General Whr asuaZby Estima Vtion M0deZ The Rand Corporation For Official Only y U Briefing on Attacks Senate Hearings befOre gthe Subcommittee on Arms Control International Law and Org-anizati on of the Committee on Foreign Relations 11 September 1974 38e result in fatalities due to prompt effects of about 0 15 percent of the U S population But an attack with twice as many l M$ weapons On 93 air bases including the dispersal bases has also been estimated to result in fatalities of 10 percent or if the weapons were surface- burst to get the tonways between 7 and 25 percent depending upon the winds Thus the estimates of collateral damage for attacks upon the U S ICBM or bomber forces are comparable both in level and I variability If weapons were surface burst at each of seven sub- marine berthing sites the fatalities due to prompt effects are esti mated at about 0 1 percent If the attacks were limited to a single weapon on each of the two CONUS bases for missile submarines i the fatalities have been estimated to be on the order of 0 05 percent of the U S population I U In sum the estimated civil casualties associable with an attack upon each of Our major strapegic offensive force elements is jhighly dependent upon the assumptions of the-attack and upon uncon trollable variables The variations are sufficiently large to becloud fany sharp comparisons between strategic force elements Attacks upon the missile submarines in port are estimated to result in fewer fatal ities than attacks on the ICBMS or bombers principally because fewer targets and weapons are involved But as a general proposition it lean be said that for comparable weights of the attack the estimated casualties associable with each force are likely to be closer to each other than the range of estimates that can be found for any single I farce element Thus the fault or virtue of the ICBM force depending upon the individual viewpoint is that an effective counterforce attack is likely to require a very heavy attack Whether that should be viewed as a deterrent to attack or as a danger from attack is the pivotal point 'of the safety issue Costs $97 The cost of maintaining the present U S ICBM force does not appear to be a contentious issue The'Minuteman hard silo deployment 5pas engineered_with low operations and maintenance costs as design_ Iobjectivesq The evidence of that effort can be seen in the anndal' operating cost of about per Minuteman silo es acmpared With fer each Titan 2 Ewith the continuing'R D programs for modernizing or improving the g This Page is Confidential 13931-- U Mbre visible ahd controversial Costs are those associated ICBM force While specific programs such as those for improving the capabilities ofEMinuteman 3 have gained visibility he E 'cause of their costs their Opposition is mere likely to derive from policy implications than costs The total and procurement progr ms in support of the 108M f orce are small in t he cIonteXt oEf strategic Ex EEforEce expenditures but they are large enough at- about five hundred Em1111on dollars Ieech year to revoke debate during the fundingI cycles iE U One View 15 that these programs should not be funded since lend-based are becomlng absolete s 3110 funding mu-1 be betteEE ldevoted to the development of weapon systems-which promise a ledger Ilife1 i2 1 U An opposing View is that the land based IGBMS will he re -E gtained indefinitely beceuSe of their capabilities and despite present Egend contested coecerns about their future survivability It is heid ' 5that technical and developmental problems Will contin e to-arise ir011- E the changing operational environment of theIfuture and that ad ptatip I fto these changes reQUires a vigorous and force modernizetionI EE 'programL 'jU S ICBME force either fer opera t iEons or for modernization programs sow it'doesEnot appear that the the preSentE 1 i 1 i' Eare crucial issues Rather it seems likely that the costs of the gpreSent_ for e by comparison with the costs for other sItrategic force Eelements are favorable qualities The costs for ICBMs may become a crucial issue only if a major develoPment program is sought for a Ijnew missile for neW basing or both 407 ICBM FORCE IMPROVEMENT DPTIONS U A very large number of technical options have been proposed for the improvement of various Specific aspects of the ICBM force These-options represent possible responses to the issues outlined pre viously collectively they define the technological future possibilities 5 for the force U The options described here range from relatively minor mod ifications of the existing force to the development of new missiles and basing concepts The objectives of this display of options are to illustrate the breadth of technical responses to issues to outline the major proposed alternatives and to indicate some of the fundamental pros and cons The options are not presented as 1 I preferred technical solutions any selection of options must be based on an evaluation in depth I U The options are organized here into four categories The first two options for improving force survivability and capability _are discussed primarily with reference to the existing Minuteman sys tem but many of the options would apply equally to any folldw-on 'system The third category encompasses options for the development and deployment of a new advanced technology ICBM and the fourth cate gory covers the options for the redeployment of the force in new basing istructures i U Not included in any of these four categories are options oriented toward elimination of part or all of the ICBMs They include reducing or eliminating the force by deliberate steps as well as per 'mitting obsolescence through neglect While these options may be re eponsive to some points of View on the issues Outlined previously their evaluation does_not depend upon the technical considerations within the scope of this review ENHANCEMENT OPTIONS The possible options to improve force survivability are dis cussed here in reference to surviv abilities w Options'for inproving in flight Survivability against i silt 9 31 pindown anay and environmental hazards are not discuSSed here bee cause both the problems and possible countermeasures are covered by existing programs Rebasing options are discussed separately beginning on p 60 Improved Prelaunch Survivability U The options for improving the prelaunch survivability of the qurrent ICBM iorce are not numerous As a result of the SALT agree-5 on mEnts two major options to improve Minuteman Shrvivahility are not now available passive defense meaSures are limited to existing silos and active defense is banned However sin ce the ABM treaty Can he 3 terminated by either side on six months not ice active defense remains an important potential option for improved survival In addition to improved silo hardness and the technical requirements for a capability to launch the force on attack assessment our discussion of options for improving prelaunch survivability includes a controversial proposal for exotic defense measures which would create a lethal environmental cover over and in the defended arses 155' Hardness Upgrading The Minuteman silo system hardness is EO 13526 Section 1 4 9 Section 3 3mm 1 3 isolation system presently is believed to control the comp osite system 3fhardness-3 the silo structural elements are harder One Option for 3 furth er hardness upgrading is still further improvement in the missiIe 'gshock isolation system with perhaps compatible improvements in cer 3tain other facility elements 3 $93 Missile caniSterization is one very promisin g possibility 3or fincreasing the hardness of the system in place and providing for launch mode flexibility Studies have shown that a common caniSter is fea51hle sfor the and its pessible growth versions for both silo and some mohile basing modes The canisterized missile can be shock isolated to about twice the upgraded silo hardness The coldalaunched canister is also effective in protecting the missile against both the - U Reported vulnerability numbers range from 41P6 to 45P5 re- fleeting different estimates and different damage levels s42r debris environment and silo tilt that may result from a nuclear attack The prinCipal question is whether upgrading hardness alone is a worth while counter to the anticipated threats unless it is done as a part I of a more extensive program to improve force survivability U Hard Site Defense While banned by the ABM Treaty hard site defense remains a potential option_for improving the prelaunCh survivability of ICBM forces The effectiveness of hard site defense is largely determined by the interplay between interceptors and the target kills occur only through RV leakage until the interceptors are exhausted thereafter the attack can proceed free of defensive i interference IWhile influenced by the RV interceptor allocation doc trines and capabilities target kill through RV leakage is generally i not very effective Any reasonably effective defense system mill let only a small fraction of the RVs of any attack wave get through until i the system is depleted U Thus to be effective against hard site defenses the attacks must enhaust the interceptors However this is not simply a matter of numbers because of certain selfulimiting effects First within a given throw weight the number of RVs can be increased only by dividing fthe'payload into smaller and smaller warheads thus reducing the kill effectiveness of individual RVs unless compensated for by greatly ime proved guidance accuracies Second and perhaps more important multiple attack waves are required to exhaust several interceptors at each silo Depending on the RV leakage rate some RVs will kill silos but they will also form fireballs growing to nuclear clouds laden with dust and debris ultimately forming a high altitude dust cover over i the battle area The seriousness of these interactions will increase with each succeeding attaCk wave U In sum the calculated effectiveness of hard site defense is generally attractive until the defense is eXhausted and the processE lof exhausting several interceptors per site by multiwave attacks may be self limiting in its effectiveness L f' The potential effectiveness of hard site defense of Minutef man is illustrated by simplified calculations in Fig 8 Optimal or preferential defense against uniform attacks and optimal attacks Average namber of RVs targeted per siio ft Interceptors RVS - defense Optimal effective detonation per site 10 ft Interceptors 6 per silo Optima - defense 1000 2 5 800 7 Optima 5 a defense 4 3 600' U1 2 Optima 400 offense 35 200 Optima ft ofTEnse 15 Interceptors RVs Fratricide 1imit 'No limit f31000 ft Interceptoxs 2 800 per siTo Optima a defense Optima offense 0 3g offense 5 Fig 8_4Minuteman hard site-defense effectiyeness as a function of heavy ICBM MIRV payloads U 1000 4195 siTos attacked by 250 heavy ICBMs each with to 36 basic Reinr 0 9 RV leakageeo 2 10 AVerage number of RVs targeted per 5510 e44 'against uniform defense interceptor RV allocation doctrines make a sizable but not a drastic difference in the outcome As is shown in- the upper graphs the Minuteman force cannot be annihilated unless the rdefense is exhausted a significant fraction of the silos will snrviVe even if the effects of fratricide are neglected This is caused by the self limiting effects of dividing the MIRV payloads into smaller Eand-smaller yield RVs Attempts to exhaust the defense as shown by' 'the lower graphs bring out the question of how many attack waves icould get in without serious kill or dispersion of the RVs It is now generally accepted that two waves are the limit if sites are undefended yWhile more waves might be possible against defended sites the one-in five leakage of RVs assumed in the illustration results in a detonation Ifand possible closing of penetration time windows at most sites after a few attack waves As an upper bound the dashed lines in the illustra 5tion show one effective detonation with undegraded CEP at each silo Hard site defense can preserve even under this limit assumption a _sizable fraction of the Minuteman force cepecially at larger CEPs Smaller CEPS could be countered by more interceptors the exhaustion of which may not be possible because of the fratricide effects U Launch on Attack Assessment A credible capability to launch the ICBM force on attack assessment requires systems for assessing the attack and then implementing appropriate launch command and targeting procedures The main objectives of attack assessment are to determine gwith high confidence that an attack is in progress to assess the nature 'and intent of the attack and to provide decisionmakers that information in time to act An attack assessment system would consist of surveil 3lance sensors communication networks capabilities for near-realutime data processing and display and capabilities for data integration and analysis With current sensors the potentially available information itimes for attack assessment are shown in Table'4 $97 It has been estimated that Minuteman launch procedures could be modified to permit the missiles to reach safe altitudes in about seven minutes after a Presidential decision to launch As is seen in Table 4 attack assessment is potentially in time to permit the'Minute man to escape ICBM but not SLBM attacks on the silosg Table 4 - SURVEILLANCE INFORMATION TIMES FOR ATIACKS 7 BY AND ICBMs SLBM Information ICBM Information Time rom Seviet_ - i Launch min System Content System Content 5 Sec on m Section segmg I i 2 A130 from ether sources 'including bomber pilots 231 3% i 5 U Attack one input to the deCiSion Pr0cess Other inputs may be the yrevailing wo ld gsit atioh ahd information available from intelligence sources As ah Eaxteck develops ever time assesSment informatics can assume two as l peCtS 'FirSt the Strategic nature and purport of the attack how 2 imany attackers from where going where and'when and Second thEE tactical particulars of the attack which depending on the quality 90f the attack assessment system may include the identity of the Spe% cific target attacker type and time of impact i U Because ei the relatively short times available a credible Edecision_process must include a preplanned set of decision criteria iinVolving at least two considerations 1 the attack assessment - thresholds for considering launch commitment and 2 the level of iconfidence in asseSSment information for launch decisiqn The first Vmay weigh the cdnsequences of launching Versus not launching the tsecond may require fer example confirmed reports from sevexal infof- mation sources of numerous Soviet Warhead detonations in the'H S 3heartland before the decisign tq launch is made 97 The credibility of the ms capability to launch ICBMS on -r ethereal Will also depend upqn having a credible targeting plan for the force that is launched In the absence of a good-hardr itarget kill capability missile silos are probably not attractive targets Attacks on air bases C3 facilities and suppression of air _defenses to permit bomber penetration might be a more effective use of resources Good hard target kill capability single-RV proba bility of target kill greater than one half may permit effective attacking of missile silos in a counterforce exchange especially if ithe attack assessment system can provide empty hole information for fuse in rapid retargeting of the force Insum3 launch on attack assessment can be technically imple mented as a credible strategic option The foreseeable technical problems are that the required warning and detection Systems are rela tively vulnerable to precursor nuclear attacks and the available'warnu ing times are not sufficient againSt SLBM attacks either pindown attacks or attacks on silos L97 Environmental Defense Systems Environmental defense has been used to deecribe the proposed use of deliberately timed nuclear Idetonations in the defended area to generate nuclear clouds which might serve as high altitude protective covers over the area A related con cept is to use the highmintensity neutron flux shields from relatively Small yield nuclear detonations as point defense systems Such pro j posals have been considered by some as potential emergency defense toptions for the Minuteman LSK The envisaged nuclear clouds would consist of dust rain and water particles forming an erosive environment that could destroy orf degrade the accuracy of incoming RV81 To be most effective the cladds 5would be formed by heavy yield 5 MT or higher surface or shallow vburied bursts For Minuteman silo deployment densities one such burst is estimated to protect about 7 silos at 5 min and about 13 silos at flO min after detonation by creating an environment lethal to 53 9 Mod a RVs Hence a few defense detonations per wing could protect a sizable number of Minuteman silos against massive attacks of nearly simultaneously arriving RVs Environmental defense concepts could be developed to a point that_wou1d permit their rapid deployment in the event_of some sudden --SEGR-ET- r 721 and unetpected deterioration in the U S strategic deterrence posture In this sense it might serve as a hold and inexpensive insurance policy to buy time for other improVements in the strategic forces The obvious major disadvantage is the requirement to detonate a submi stantial friendly I megatonnage within the northern regions of the a prospect fraught with strong political and emotional overtones although the collateral effects from clean defense weapons might come turd o Postattack and Enduring Survivabilities ipare very favorably with-those from massive attacks 0n undefended tar gets In addition environmental iefense would be critically dependent upon highwconfidence attack assessment systems because of detbnationlfi timing problems and limited shiel endurance unless the sh1eld is re- onewed by additional detonations U The 0ptions to improve Minuteman launch availability in the gpostattack period include I improvements in the survivability aha reliability of the standby power units to extend ICBM launch endurante past the fixer day and 2 dormancy of the missiles to reduce main - tenance an poetattaok power requirements thereby extending the sure include hardening of the external generators and fuel supplies now i durance to many weeks or even monthsi i 93f Potential improvements in the existing standby pwar systems i fmuch softer than the silos ans better starteup switch QVer reliability Another option is to use small nuclear power reactors or h_igh energy gdensity heat sources with an energy conversion system within each silo iThese options could increase the launch availability of the force at the end of the battery life but they cannot forestall the eventual system degradation due to limited postattack maintenance 87 Dormancy of the missiles is a completely different approach to maintaining the launch ayailability of the surviving ferce Onlyg minor changes in the existing system hardware are required to permit the miSSiles to operate in either the active or the dormant mo e When dormant all are turned off except those of command and control and perhaps the sump pumps in wet sites The missiles can 4 - Lbs returnedte scti te alert status In 6 to 10 mine f sass L f' Dormant operation of a large fraction of the Minuteman force would eyercome both the standby power Survivability and Ire1iability and the postattack maintenance problems A sma11er fraction of the force could be operated in an active mode permitting rapid reaction The Minuteman guidance systems have been dormancy teated with excellent results However past Air Force evaluations of partial dormancy have brought out differences of opinion about the effects on system accuracy reaction time turn-on failure rates and manning requirements that 3 remain unresolved at this time CAPABILITY IMPROVEMENT OPTIONS U The options to improve ICBM capabilities are discussed here i in terms of improving the capability of the force to execute major I strategic tasks countervalue CV Counterforce CF and limited 1 strategic operations L80 Most of the specific options considered would improve the force's capability to execute more tasks than one For example throw weight increases benefit both CV and CF tasks and guidance accuracy gains are beneficial in CF and L30 tasks Since the 5103M capability for CV tasks is not controverted except on surviv ability grounds the improvement options are discussed first in refer ence to CF tasks with some options having overlapping implications for other tasks This is f0110Wed by a discussion of options specifi- cally oriented toward improved capabilities for L50 tasks U Another group of possible options not discussed here inr -volves improvements in penetration of enemy defenses Since largeescale active defenses are currently banned by the ABM Treaty ghowever future availability of these options on timely bases requires a vigorous program to maintain U S technological superiority to avoid technological surprise and to inhibit Soviet abrogation of the treaty I U The options associated with a new missile are discussed separately beginning on p 56 Improved Counterforce U Several options are available to the capability 9 5 the present force in counterforce attaCks through better target coverage and hardeterget kill ootential These 'i RES Unauthorized discins bled to the and crimina tions Handle as Restricted - Data In n- dissemination Section 144i '1 Aft n i throw weight increasing the yield from throw weight improving accuracy and going to an all Minuteman 3 force g5 Additional options would permit a more effective use of hard target Kill capability in counterforce exchanges One is to pro vide the ICBM force with the means for effectively using bomb damage assessment EDA and empty hole information during a Series of ex i Changes This requires a capability'for very rapid retargeting of R s Explicit retergeting is one way to reduce tetargeting times it mayg also be useful in Advancing technology may permit the develoP i ment of self-contained with terminally 3 guided RVs $95 All Minuteman 3 Force The U ICBM fq-rce would be Signifi cantly more effective in CF Operations if Minuteman 3 missiles replaced 5 the Minutemen 2 Figure 9 shows the single Sh0t kill probabilities of i Minuteman 2 and Minuteman againSt Soviet missile silos With currently'teported CEPs each of the three Mk l2 RVs of Minuteman 3 i 4 is-a more effective hard-target killer than the single-Mk llc of Minuteman 2 so each of the present Minuteman Bs equals about i three Minuteman 25 in effectiveness Projected CEP improvements and the new RVs under development will increase the Minutemen 335 effectiveness further two Minuteman 2s muSt be launched against a i i target to produce about the same kill probability as that achieved b 7 each of the three RVs of the Minuteman 3 'Hence each of the Minute man 35 will equal about six Minuteman 25 in effectiveness But as is I seen in Fig 9 significant kill capability against the new hard g'missile silos can be achieved only with Minuteman 35 at the projected aided by the new RVs 585' ImproVed Throw weight Range 'The5Minuteman'S throw weight and range can be improved by further evOlutionary modifications to 3 fthe missile similar to those made in the past as completely new missile of the same weight and within the dimensions of the Minuteman f 3 but using advanced technology would about double its payload to $33500 lb at 6 000 mis For evolutionary changes of course the gains wogld be someWhat lessg bnt the options are numerossn -ns an e1amnlei a 81' ng e shot damage probabj i ty MM-B New RV 1 0 CEP 600 projected 500 projected 1000 nur ent 1'8'00 projegted 100 0 current New 'h an A current 70 2 38 34 0 42 44 46 '48 50 yu'lnerab ity number P6 - and hard target _damage_ca_pabi3iities U e511 1 In one inuteman 3 improvement OptiOn using a new second stage and re j placing the first stage unzzles with a single nozzle Would indrease the missile' a throw weight to about 2 500 lb Improved Warhead'E ficiency The current development program is using advanced warhead technology to about double the yields of Minuteman 3 warheads within the existing Mk lZ weight and dimensional 1 constraints A similar option is available to double the yield of 5 the Mk llC RV on Minuteman 2 at no appreciable increase in weight 11 U ICBM Accuracy Improvement The options for improving thei accuracy of the ICBM force may be divided intOVthree broad alternatives i 2' Continuing _inprovements and refinements of the current a11 inertial systems Development and exploitation of external artificial navi gational aids and DevelOpment and exploitation of sensors utilizing external natural phenomena aa navigational aids i U These alternatives are not mutually eXclusive of course 3 The use of external navigational information has generally been pro 3 posed as an adjunct for inwflight updates of the inertial guidance nof maneuvering reentry-vehicles for trajectory adjustments 3 asystem reducing the guidance system errors or combined with the use Zoduring the reentry and terminal phases also reducing or eliminating the nonguidance errors U 'The currently ptoPosed guidance system concepts in the above three categories and their potential accuracies are summarized in i Table 5 The all inertial systems depend on accurate knowledge of the 5 launch pointis initial conditions If not accurately known as in many m0bile systems guidance aCCuracies are correspondingly degraded In general Systems using navigational aids do not require launch point information and their accuracies are largely independent-of the mise 5 sile'basing model Stellar inertial systems fall in between since the star scanner information can reduce the initial uncertainties in i the launch point oosition and platform alignment but not in the velocity vector their accuracy will depend Omaha basing mode and honnwell othe initial conditions are known -52 Tab 1e 5 OPTIONS FOR IMPROVED ICBM ACCURACY U Launch Point CEP ft at 5 500 mi Type Initial - of Conditions Weapon Approach System RV Required Guidance System As seen by Allminertial Proponents RV Yes 115-260 380-450 Skeptics RV Yes 350 500 500 700 Post boost RV No 150 200 300 430 Radio overlay Late midcourse RV No 80 110 240 380 GPS to reentry No Nil 70-150 Depends on how well Stellar inertial RV Yes but initial conditions are known Environmental Terminal Tracer No Nil 200-400 sensors Guidance Radar area No Nil 80-150 Optical No Nil 30 80 J r All Inertial Guidance Systems Opinions differ on how much further improvement is technically possible Skeptics see limits in the ability to maintain the required dimensional stabilities to field calibrate accelerometers to the required accuracy and to transfer performance in the laboratory to performance in flight The advantages of all inertial systems are that they are self contained that they are impervious to countermeasures and that their technology base is well established 59f External Navigation Aids Systems using a radio overlay need a radio-measurement aboard missiles and a ground or satel lite based GPS system of transmitters Although either system can be Lused for post boost and midcourse measurements only GPS global posi- tioning system transmitters can reach for trajectory corrections during reentry The use of radio aids complicates the system and may thereby reduce its reliability While the ground based transmitters should be relatively inexpensive and difficult to countermeasure the GPS transmitters may require extensive development may be more easily countermeasured and will depend on -- Emv1ronmenta1 Sensors Various sensors could be- used in 2 terminal guidance systems to establish a position fix for The canstraints imposed by Weather and lighting vary with the sensor as does the obtainable accuracym Terminal guidance Systems will require a sensor guidance and c0ntrol and computer package in each g with a corre3ponding reduction in the warhead yield They are more complex and @robably lees reliable than the yore inertial or radio inertial Systems and because they'mmst operate in the target area 3they may be more subject t0 countermeasures Terminal sensors will 3 - ales require extensive acqu1e1t10n and reductibn of t arget data they will complicate the problems o_f rapid and flexible retargeting of missiles ' ZExplicit Retargeting of RVs EXplicit targeting'of ICBMs by latitude and longitude is believed to be the most direct and effic uh ient method far reducing the retargeting times probably t o less than gnaw computer software and perhaps a new airborne computer Combined 11 a minute If deve 1oped for the'Minuteman 3 missiles it would requ1re 3 With bomb damage asSessment information explicit retargeting capa bility would permit rapid reallocatidn and latnch of threatened mis-E isiles on attack assessment the present Command Data Buffer is too isiowj It could also be useful in LSOs against targets for Which there were no precomputed target data J af Guidance Capability There have been several prop0sals to use MIRV buses as platforms for$ Esensors and as data links to give the system a near-rea1 ftime reconnaissan e capability for bomb damage assessment or for term- Zinal gu1dance of its or both The concept envisages a high -resolution aperture sid e-looking radar for all weather - target detection data trans mission Via bus based data links or spec ial data relay vehicles and central dat a processing in CONUS or aboard a C3 aircraft Vm 1 An important aspect of this concept is its potential use for recce strike missions against either fixed or mobile targets Sur vijing elements ofua fixed target set conld be retognized and attacked Mbbile targets such as land-mobile ICBMs er navallvessels could be attacked given prior knowledge of their approximate positions Limited Strategic Operations J26 The main requirement in LSOs is for the weapon to execute a desired task with high confidence while limiting undesired collateral damage This may require positive 63 quick response flexible target ing efficient hard target kill and high confidence penetration I i Some options to improve counterforce capabilities improved guidance accuracy and explicit retargeting respond also to LSO re quirements Other options are available specifically to improve capabilities Discussed below are options to minimize collateral i 3-damage and to rapidly reload silos to maintain an unimpaired second strike capability Also treated is the concept of an elite ICBM force wherein a part of the ICBM force is equipped with special enhanced capabilities for prompt and flexible use in LSD Options To Minimize Collateral Damage One option to mini mize collateral danage from L305 is to minimize the yield required to 5 achieve a desired damage probability This can be done most directly through improved accuracy However since the targets of interest in LSOs may range in hardness from soft to superhard targeting flexi Ibility may require the use of single RV missiles with a variable yield warhead Both the yield and fuzing of the warhead could then be iselected on the basis of the target hardness and desired damage ex- pected CEP and collateral damage considerations 99f Another option for reducing collateral damage is the use oi earth penetrating RVs Fallout and blast effects are large1y_eliminated - - - the hard-target kill effectiVeness of the buried RVs U Silo Reloading Capability A capability for silo reloading would permit rapid replacement of nissiles launched in_LSOs and ther fore would maintain a continued L30 and an unimpaired imissiles and equipment and for crews to rapidly reload the silos alify reloading the silo mm yum 155 retaliatory capability The importance of this Capability depends on perceptions of the size and timing_of L505 535' The hot exhaust gases of missiles launched from current oper ational silos-would destroy much of the equipment in the silo The i refurbishment of a silo has been estimated to take abOut one year and to cost abonthl million An appropriate hardware proteCtion syStem icould be designed that would cut the refnrbishment time to a few days gPlans and procedures would also be needed to provide for Ieplacement i 92 Clearly the resource requirements of silo reloading depend yon how many missiles must be reloaded how quickly While -the proposals lfor cold-launched encapsulated missiles are motivated primarily by jinterest in_ increased throw weight and hardness they also could simp ' 1 59 Elite ICBM Force This is a concept to equip and maintain Ia part of the ICBM force with special enhanced capabilities appro - priate to the prempt and flexible use of ICBMs in LSOs and perhaps leven in theater nuclear war Even though L505 are probably the most idemanding of the strategic taSks in ICBM capabilities these demands% do not include severe requirements for initial or enduring surviVa1 gihus the present silo basing seems quite adequate for an LSO configured ielite ICBM force Larger Soviet attacks on the elite force imply iescalation of nuclear violence to a level calling for responses beyond limited strikes with Special capabilities $97 In concept an elite ICBM force could be constituted by Eulating special procedures and by providing special system capabilities ito a designated part of the Minuteman force Among the-special pro f CEdures the elite force might have appropriate C3 systems and links to higher commend echelons and special launch enable procedures to permit rapid responses to the National Command Authority The elitei force might be given priority in all planned improvements in the force such_as the Command Data Bn fer being deployed today For targeting flexibility precomputed target date on suitable LSO targets could be fkept current at all times If guidance system aging is shown to he an pimportant factor in degrading accuracy special r plecement procedures 756 Icould be used to keep the guidance systems young To deter Soviet attacks against the elite forCe the force could be protected under the Safeguard umbrella by designating either all or a part of Minute man Wing VI at Grand Forks AFB as the elite force 1 The special capabilities that could be provided for in the elite force include RVs designed to reduce collateral damage and some one-RV payloads with numerous height-of-burst options Explicit re L targeting Could be provided to enhance the flexibility in the selection 3 of targets It may be possible to improve the confidence level of the performance of an elite force by techniques snob as the Trajectory i 5 Accuracy Prediction System TAPS to determine whether the missile 5 guidance is good To maintain both a continued LSD capability and an E unimpaired retaliatory capability the force could also be provided 9 with a rapid silo reloading capability OPTIONS U An important set of options for enhanced ICBM capabilities_ is associated with deyeloping and deploying a new advancedvtechnology imissile These options open up possibilities for significant increases in throw weight and range for improved target coverage and hard-target kill capabilities while providing opportunities to incorporate various detailed improvements in both the missile and the reentry systems g r While numerous concepts for new missiles have been examined the principal differences are in 1 the deployment mode deployment in existing silos rebasing or a multimode deployment and 2 the front and selection or optimization of the MIRV payload Deployment modes are important because of the Weight constraints they may impose on new missiles In general most rebasing systems can accommodate large missiles concepts for offroad mobile systems have specified missile weights up to 270 Klb Road-mobile systems are the apparent exception in unhardened vehicles they would be limited to about 40 by highway legal load limits I U New missiles deployed in the existing silos must of course be dimensionally compatible with the silos The several options and I constraints are outlined below A_subsequent section explores the payload yield combinations possible in the various missile sizes accommodate missiles considerably larger than Minuteman 76 Rib SECRET 11171- New Missile Options for Retrofit S Compatibility'With Eristing Silos Minuteman silos Can m- W-a- wm - 2 Missile weight limits are controlled by gr0ond transportation The heaviest object that can be moved over roads special permit is 90 itp 100 plus the transporter erector If this were the weight illimit for assembled missiies a payload of abOut 4 000 to 4 500 lb could be expected If that weight were the limit for unsegmented i Eifirst Stages corresponding to a total missile weight of about 150 nglb the palead would be about 7 000 lb Larger solid propellant i missiles must be transported with segmented first stages and assembled j at the launch facility The 1argest missile that can be assembled in I an existing silo w1thoot sacrificing the upgraded silo hardness has grbeen estimated to be in the 250 to 300 class S Hot Flyout Versus Missile Canisterization The size of new missiles depends on the-desired launch mode Hot flyout from the existing silos is possible with missiles up to about 100 Klb Larger missiles must be canisterized for cold ejection launch wa ever- canisterization may be desirable even for smaller missiles iibecause of deployment mon flexibility a common canister system Emay be feasible for both silOHbased and land mobile missile systems sand enhanced hardness a-canistet system can be eas11y shook Empunted and made less sensitive to the effects of surface or crater i debris and silo tilting C Solid Propellants versus Liquid Propellants Solid propellant gmissiles Will be generally preferred for mobile deployment for con- venience in groundHhandling and transpor-tation Liquid-propellant missiles may have some advantages in retrofitting existing Silos if rthe missiles are very large because the one time missile transporta i tion and assembly problEms would be simplified S Interim Agreement While the Interim Agreement prohibits the conversion of land-based launchers from light into heavy ICBMs it does 3 permit force modernization Ihere is an initialed statement that in i the process oi force modernization and replacement the dimensions of landzbased ICBM silo lauotheramdl 1191 significantly increased SEGBET i There is also a common understanding that the term significantly increased means that an increase will not be greater than 10 15 per cent of the present dimensions of land-based ICBM silo launchers I There is no agreed interpretation of the term heavy There is only a unilateral statement by the U S Delegation that any ICBM have ing a volume significantly greater than that of the largest light ICBM now operational on either side is considered to be a heavy ICBM The largest light ICBM is the Soviet SS-ll with cylindrical envelope volnme of about 3 200 ft3 While the term volume significantly greater has not been defined a lS percent increase analogous to the above mentioned silo dimensions will give a volume of 3 700 ft3 correspond ing to a missile weight of about 195 th and a payload of about 9 000 Ealb This may be the largest light missile possible within the 0 8 interpretation of the Interim Agreement Illustrative New Missiles and MIRV Payloads 133 On the basis of the above considerations and assuming the 2 Air Force s MK Program technology and 6 000 mi range some missile weight payload combinations are listed below Weight Payload Klb lb Weight Criterion 40 1600 Heaviest road mobile missile soft transporter launcher 80 3500 Minuteman 3 weight class 100 4500 Heaviest assembled missile road bridge transportable 150 7000 Heaviest missile with unsegmented lat stage road bridge transportable 195 9000 0 8 interpretation of heaviest light ICBM under Interim SAL Agreement U The MIRV payload yield combinations possible for the above missiles are illustrated in Fig 10 Numerous MIRV payloads are avail able for the larger throw weights their hard-target kill effectiveness depends of course on weapon accuracy The yield CEP combinations I necessary for a 0 9 kill of typical Soviet hard targets are illustrated in Fig 11 v combinatiQ S 6835 u 1 1- I run i illitl-f 33% Weapon storage 3 37PG 533-9 38M- 35-1114 296 55 1 3 1 896 New hard 5 1 105 1 5IP6 Weapon stdrage w'zr i rlr in m3 104' Nga pon We KT WFir iiYi fdfCEP combinations of reliable weapo hs for 0 9 dm age Prqbabj1ity agafnst selected hard targets LU 1 3 urn - w m j a' Some MIRV payloads for hard-target kill are shown in Table 6 WEapon system accuracy is a primary'inputi the CEP yield combinations shown are required for 0 9 kill of the new hard Soviet silos 48P6 or about 3 600 psi at one MT assumed here current intelligence estimates are not available The number of such RVs possible is then shown as 1a function of missile payload 1995 Table 6 NUMBER OF HARD-TARGET KILL RVS VERSUS MISSILE PAYLOAD U 0 9 kill of 48P6 targets ft Yield KT ICBM Payload 300 250 600 1700 900 5000 lb RVs RVs RVs 4500 8 10 3 12 l4 1 9000 14-16 5 5 2 ICBM BASING U New basing concepts offer the most exciting and decisive 'determinants for the future of ICBMs Over the years a large number have been proposed studied and debated Most of the concepts have been put forward as means for improving the survivability of the 1030 force But beyond that common objective they are not easily resolved into an orderly array of possibilities Basing concepts are most often categorized by design features fixed or mobile silo shelter or pool road rail or canal transport etc These classifications are descriptive of the required hardware and facilities but they are not rvery helpful in comparative evaluations or in assuring comprehensive consideration of the alternatives 0 Here a more fundamental approach to ICBM basing concepts and their classification is appropriate so we begin with some gen eral considerations of the parameters that ultimately define the sure Vivability characteristics 0f the forcss These peraasters Provide a- - SEER-ET- age is Confidential asia - witgag 111 5 are diverse proposals for-new basing lmay be generieally classified and then Systematically reviewed for L their teehnical operational and economic features V Some General Characteristics of ICBM Basing U The most important single parameter defining the Survivar bility charaCteristics of-any basing is the kind of target geometry' presented to the attacker that is whether his targets are point '1ine or area target arrays BeEp space basing of ICBMs would theeretically constitute a volume target array but s h basing is now prohibited by the Outer space Treaty of 1967 The target geometry the array siZe number and spaCin_g of points of lines or 3 area size and the target hardness oi a given basing system determine both the atteck_requir ments and the inherent servivability of missiles Edeployed in that basing system These fundamental relationships ar-Q illustrated in Fig 12 for three different target geometries i U Each of the curves in Fig 12 represents the_minimum survive _ing fraction of a target array as a function of array size- For mis% siles distributed randOmly in the target arrays this is also the gminimum expected surviVing fraction of the missiles deployed The l' larray sizes are all normalized against an attack by one Soviet heavy EICBM and scale directly with the attack size number of 30 5the figure illuStrates survivability against fixed throw-weight threats a vi The payloads are theoretically Optimized for maximum target kill henCe the number of RVs and their yield vary from case to case as a function oi target geometry array size hardness and the attacker's fear 91' The Upper curves of Fig 12 show the effect of on sur 3 lvivability plotted for target'hardness It can be seen that i target geometry determines the relative importance of attack accuracy point targets are very sensitive to CEP improvements line targets 'somewhat less and area targets hardly at all Array size increases' up to a point of diminishing returns such a point can The determined for each target geometry hardness and CEP 1 5133 135421 g ua$13943 BugagAdng mnmgugw 8-8 Point TargetS 41P6 Lin fTa QEts 841P6 31509 900 300' ft 88888 15_881248 Number f 11199158 Area Targets 41P6 One tb 36 RVs per Re11abi-1itynr 0 9 Max 2 RVs p_er point target CEP Re1 degraded W1th 1ncreas1ng numb r VN ft 41P6 35P68 gehgth 9f Line $1 29 of Area n m1 5 Fig 12-5urv1vab11it of target sets attack d by one optimal1y-MIRVed Soviet heavy ICBM 62 1 593 129' The lower curves of Fig I2 show the effect of target hard guess on survivability plotted for the same 900 ft The diffege ences between line and area geometries are less pronounced- but it is Sapparent that eras targets are more sensitive t o hardness than point-I targetst In sum po1nt targets are more sen31t1ve to and benefit flees from harden1ng than other geOmetries ConVersely a area targetsl5 Qare relatively immune to improvements and can benefit mo re direetly- -from 1ncreased hardness The characteristics of line targets of course lie between the two 7 - U While the target geometry presented to t he attadker 1s a j'iba31c determlnant of surv1vab111ty the riEh Spectrum of miss11e'bas1ng concepts deriVes not so much frOm differences in target geometry as 1t does from the d1verse means for any given geometry upon the attacker QhVieusly is not an area or line target unless the ghasing scheme makes it so by generateng and a geometrlcaI 1 array that must be attacked to kill the missile 7 Ej U The most common means for generating a credible geometry is 4 through _sOme form of missile mobility usually by either redeploylng for being able to redeploy the missiles to any arbitrary 1n the intended target array The modes of mbbility include con- tinuous moVements of missiles 1ntermittent movement initiated 1n Ururesponse to either intelligence cycle times or attack warning and no mevement after initial deployment in the array 1 U The target geometry generated by mobiIity is subject to coI an Vlapse through the determined efforts Of the attacker Reconnaissance and -surveillance actiVitie$ may be able to resolve missile locat1onsr within the 1ntended target array and provide timely targeting informer gtion for an attack maintaining a credible geometry 1n t he face of gsuch efforts may be acc ompliShed by various tactics- applied either tot the missile movements or their sites Such credibility tactics 1nc1ude concealment deception or even overt operations U The foregoing general considerations are basic to all basing ECOnceptS' they provide a framework within wh1ch proposed basing schemes can be identified and classified Table 7 meet of the fam111ar 3 basing c'oneepts systemat1cally arranged in a matriszhose dimensions i This Page is Unclassified 64 Table 7 CLASSIFICATION OF ICBM BASING SYSTEMS Mobility Mode Intermittent Reaponding to Target Credibility Geometry Tactic None Intelligence Attack Continuous Missile silos Shell gamelRandom Shell game Dash OVERT DUB Overt exits Air base hopper POINT DECEPTIGN Silos Decoys Shell game Decoy TLs comma Shell summed Road Road Dash Road OVERT Rail Rail Dash Rail Barge Barge LINE Roag Rail Barge Road Rail DECEPTION Disguised Barge Disguised Road Disguised On strategic warning Conce led lines Canal basin 'th f 7 Canal basing CONCEALMENT issile zen Soft tunnels No Portals- Soft 0v nc I er Offroad mobile Offroad-mobile Offroad mobile OVERT - VTOL hopper Air mobile Strip Air-mobile Airh alert borne alert Sea sitter BMS Undisguised AREA - Sea sitter Dash Offroad-mobile Offroad-mobile DECEPTION dummies dummies BMS Disguised DUB Concealed out Submarines exits Submersible Barge FBM Submarines 1 w_ DUB deep underground basing BMB ballistic missile ships TL transporter launcher rm This Page is Unclassified -551 are target geometry mobility mode and credibility tactic Any ICBM basing scheme can theoretically be placed in an appropriate box in i such a matrix There are Several advantages in structuring new basing coneepts scoording to the dimensions of Table 71 Eirst it groups 3 together those concepts Which have the same fundamental survivability same target geometry same mob111ty mode to generate Mu 1 1 1 the gEOmetry and same credibility tactic to maintain the geometry Thus the comparative evaluation of concepts within the same box can be made primarily in terms of cost Second the matrix enforces comprehensive consideration of the i alternative connepts for ICBM basing The crossedwout boxas represent combinations Whi_ch seem logically inconsistent and are therefore not espected to be a source of basing options other boxes have beeA considered as possibilities for basing schemes Thus can cepts for i Tbasing tha t may be proposed in the future are expected to be variants of previQUSIy considered types rather than generically new types 1' Finally eadh filled box in the matrix represents a generio basA ing optiOn exemplified by one or more specifie proposals TheSe i generic options provide the st ructure and a suitable 1eve1 of aggre 3 5 u w I gation for a systematic review of the technical Operational and economic features of new basing for the ICEM farce Point Targets Missile silos are a familiar system of point targets with many desirable characteristics such as low operating costs prever sin e Teach silo houses a missile farce and target array Survivabilities are iequal and the force can be drawn down rather rapidly by accurate threats Options to enhance the Survivability of point targe into the categories l deep underground bases making the missiles nOntargetable by the enemy with many launch exits to Emaintain sufficient launch capability and isystems with many redundant shelters and missile mobility to main-g itain aimpoint credibility Akin to the latter is a system_of missile silos and inexpensive decoy silos except that the missiles are frog n in their 51103 and 34 Selely Q -long term deception for credibilit 66- U Deep Underground Basing with Overt LaunCh Exits Deep underground missile bases could store the missiles in virtually invul nerable facilities Since the stored missiles are nontargetable all can be assumed to survive Except for certain area target systems all basing concepts require missile proliferation for enhanced sur vivability Missiles can be launched through a system of exits each capable of multiple launch Although overt exits have the individual survivability characteristics of point targets overall survivability -'may be improved if a few surviving exits are able to launch the entire aforce A small surviving fraction of launch exits could be converted I to l00 percent survival of launch capability $97 The potential advantages of basing missiles deep underground include in addition to the physical survival of the force the possiu bility for deploying the force in compact areas unobtrusive upon the public The force could also he provided with postattack maintenance for enduring survivability Since the response times and firing rates imight be relatively slow of the order of 30 min the force may not She suitable for LSO and counterforce roles but it should have excellent stability characteristics The main concern with the concept is assur ling that the missiles can get out- much of the total cost of the system goes into building of launch exits The number of exits needed for adequate survivability depends on the threat including that of trans- attack surveillance and reattack that might close the initially sur _ _viving exits While banned by the ABM Treaty now a preferential active defense overlay is a feasible way to preserve a desired number of exits U The development of deep underground bases will require a major technology effort both to increase the confidence in and to re duce the cost of such systems U Shell-Game Missile Systems Shell-game missile systems athieve surviVability through redundant aimpoints Aimpoints could be silos garages pools or other shelters designed to conceal and rprovide hardness to the deployed missiles Hardness could be achieved Concealed launch exits are discussed under Concealment Line Target Systems beginning on p 71 25575H 2 2 us hy shelters alone or by combinations of shelters and missile capsules gDiscussed below are the two basic issues of Shell-game systems tarf get credibility and the relative Shelter-to missile cost U Ehrget systems achieve survivability Ithrough_aimpoint leverage several shelters must be targeted to threaten one missile It follows that the Basic requirement of the systems is target credibility 'all shelters must he equally credihl missiles deployed Discussed below are the four schemes listed 1n Eaimpoints to preclude the array siZe from collapsing to the number Tahle 7 tor ma1nta1n1ng Shellwgame target credibility - jj a' Overt Random Redeployment This Concept aS-sumes that the Idetectlon of m1531lest-arked in shelters e1Ither by covert or overt- - wag agents or sensors 1eads to relatively lon mm intelligence4cycle times Target compromise hy Such long ICTs could he_ countered by ran ' dom redeployment of missile transporter launchers TL with an appro I lpriate redeployment cycle time Since the detectiOn of TI movements - by covert means is expected to result in equally Tong ICTs the main threat of detection comes from orbital sensors whichchuld in prime ciple provide near real-time surveillance of TL movements Howeserg Isince TL soveme ts from'one SheltEI to a other sh0uld take only affe 'I Eminutes detettion by satellite s ensors could be prevented by schedul- jing ovart redeployment moves in darkness optical under cloud cover and optical -or- during predictable gaps in satellite I threats of detection'have been discounted SAR systems reqUire hundreds gthey can he jammed or spoofed by decoys WOuld be stationed in central shelters ready to dash to a randomly above Slnce theI attacker tr1ggers the dash at a lAll weather - day and night surveillance is possible only with faperture radar SAR or phasedwarray radar systems In general sash Eof satellites for freQueot coverage lo sin average frequency WhiIIe phased-array systems can in principle provide continuous coverage U Overt Dash Redeployment'e In this and crews selected adjacent shelter upon attaCR Warning As dash systems they reliable Warning and speed Commensurate with arailahle warning grimes HoweVEr they are also subject to the satellite surveillance 1 ftransattack mobility may be degraded because the transporters are jseparate from the missiles El'Eil 5 Eli if time of his choosing his one time surveillance requirements to track the dash are greatly reduced 0n clear days the cOmbination of a few optical sensor satellites and inrflight retargeting of RVS could make the effectiveness of this mobility mode questionable - i U Concealed Redeployment - Detection of TL movements can be prevented by concealment covers over road networks However inexpen 5sive soft covers can be blown away by light attacks forcing the system back to overt mobility Harder covers are likely to be costly v U Deception Redeployment Deception systems could use both 5 real and dummy missile canister launchers and separate transporters The canisters could be exchanged at random under a concealment cover 9 lDeception systems will be more costly than overt systems and their f $97 In sum shell game target credibility can be maintained by overt random redeployment scheduled to avoid detection prayided hose 3 ever that continuous Spaceborne radar surveillance can be ruled out either on technical and cost grounds or because of countermeasures If not target credibility will require the use of concealed or decep tive redeployment both more costly than overt redeployment Possible frequirements for maintaining transattack credibility may also affect Ethe choice of shell game mobility modes L f' Cost Effectiveness Considerations- The costeeffectiveness of shell game systems depends largely on the cost of shelters This gcan be shown by using minimax system cost criteria for sizing the force 5Unit missile and unit shelter costs are defined as all life cycle costs $ procurement and operations necessary to add either one unit eduipment missile or shelter to the force Thus the life cycle cost of a system exclusive of is the sum of HE missiles times their unit gcost and shelters times their unit cost Forces are sized to proyide a desired surviving force against a specified threat Obtainable different missile and shelter combinations In a minimax cost model the attacker maximizes his kill optimal and targeting and 3 thereby the cost of all possible combinations The least costly of f these maximumrcost forces is the minimax system cost force selected - the defender figure 13 presents some typical minimax solutions 3 I for the system cost when normalized against threats by one Optimallyg heavy ICBM - These unit system costs scale directly with the 3 attack size for example if systems With a $20 m1llion unit miss11Q cost are attacked by 300 heavy ICEMS the cost ordinate is multiplied 1 by 300 20 $6 billion a 7 liar Wmile the minimax system costs are driven up by lucrea31ng - threat either increasing throw weight or improving CEP and depend i on the desired degree of force survrvab111ty they are greatly affected by the east of shelters The edsts triple as the shelter-to m1ss1le -CEP '360 ft 10 2 299 ft - SUrV1v1ng r m15511es A Per - 14 1 attacking Unit system St U it m15311e cost -3b0 psi sheTters II I 1 I 0 02 106 08 ' 10 unit shelter-cost Unit missiIe cast 13 M1n1max systEm cast of sheII game systems normalized aga1nst one opt1ma11y heavy Seviet ICBM 2 cost ratio increases from 0 01 to 0 1 from $0 2 to $2 million in the case of $20 million unit missile cost This cost ratio is a2 basic determinant of shell game cost-effectiveness and can be used to 1 compare and evaluate any proposed system concept 87 In Optimizing shell game systems there is also a trade off Abetween the number and hardness of shelters the optimal hardness def pending on the relationship between hardness and cost or course lower hardness levels need larger shelter separation distances and larger deployment areas For example 300 psi shelters need about 10 to 15 miz area to counter one optimally heavy ICBM loo-psi shelters about twice that area These requirements are satisfied wi h_ land potentially available for shelter deployment about 10 000 mi fin military bases dedicated DOD lands and another 12 000 mi2 on contiguous Bureau of Land management land LLine Targets U Line geometry targets generated by missile TL movements over flinear networks constitute the second major group of target systems Typically overt and deception mobility concepts would deploy missiles via the public transportation systems Rail mobile Minuteman test trains were operated over the nation's railways in 1960 An important concern is the potential interface problems caused by the regular movement of nuclear weapons and the commingling of military and civil targets Discussed below are a concept for a disguised road mobile isystem designed to overcome some of the public interface problems and several concepts for concealment systems deployed over dedicated inetworks s r Disguised RoadeMobile System Some of the public interfa e problems of road mobile systems could be minimized by deploying at a gfew military staging bases TL vehicles disguised as commercial vehicles 13ince these vehicles would be concentrated and soft the system must be considered vulnerable to surprise attacks 0n strategic warning how ever the missile carriers could be flushed to dispersal locations selected from among the several thousand smaller military installations U The concept may have numerous variants - survivability from strategic warning 4 'ging might immobilize the capsules submerged barriers and oVerhead 1 751 throughput the cOuntry Since the dlngISed vehicles_ should not present 2 recognitable signatures to satellite sensors TL movements coul d re main hidden within nonmilitary traffic and the carriers would be non targetable until detected and identified This conc p t shou ld be considered as a Spee1al low cost bas ing Option using small missiles up to 40 000 lb within highway weight limits and deriving their U1 Concealment Line Target Systems ConcEalment systems would generate line geometry by linear mobility under specially built cOn E cealment covers These systems could b hardened to increase their survivability i PropOsed Cbnoepts -Proposed cdncepts i nc1ude those deploying x lsubmersihle launcher capsules in canals and Wheeled TLs in shallow undergrOund cut-and coVer tunnels and in soft-covered trenches Mis i siles could be launched from any point along the line Typically line hardness Would be achieved by hard TLs or missile capsul es rather than by a hard cover W1th intermittent or co ntinuous mobility theSe sys- ltems COuld prevent detec tion and have equal preattack credibility The main problem is transattack credibility Light attacks might re- gmove or destroy a soft trench cover thus revealing missile locations iand leaving them vulnerable to follow on attacks Canal systems may he vulnerable to cratering attacks and may drain Although such drain i it cUlvert type covers have been proposed to maintain concealment E Critics have questioned whether there is enough water or level land gfo r canal systems U Cbsb Ej sctiveness-wThe cost-effectiveness of concealed hard gline systems in analogy with shell-game systems can he examined in Eterms of their unit system costs Using unit missile costs as before land defining' 'unit line cost as all systemccosts necessary to addt g lone mi of line Fig 14 presents some typical minimax system costs iThe costs -are muCh less sensitive to improving and linevtmeissile Tcost ratio than the corre3ponding costs of shell game systems -5 300 ft 900 ft 4 Surviving 8 8 miss es 0 3 Per 33 attackmg 2525 Hhe 'Oi l i 1 0 04 08 12- 16_ 20 Unit Hhe cost n mi Uni t miss e cost Fig 14 M1iniqu system costsf hard Haneiisystems de na zed zag ainst one optimally heavy So'viet'IjCBM Area Target Systems U Area targets are least sensitive to CEP improvements and they benefit most directly from hardness Area geometry is ge erated Eby mobility On aboVe or below the ground or sea surface The type _or mode of mobility and speed requirements depends on the credibility tactics used Briefly discussed are possible overt and concealed area target systems Deception systems might take the form of real and idummy TLs on land or disguised ballistic missile ships at sea U Overt Area Target Systems Area target systems generated by overt mobility rely on speed to maintain target credibility to Iescape aimed attacks based on detection and the associatedyICT If the speed is insufficient the target area shrinks or the system becomes a set of point targets Area targets are affected also by the operatiag media land sea and air Sea basing options include undisguised jballistic missile ships and sea sitting amphibian aircraft The 23511 latter is a variant of alt moblle ICBM systems using both sea and air _media far survivability Briefly discussed below are land offroad and air mobile basing options U ICBM systeMSn-Offroadwmoblle systems could zoperate inotwo modes dash in response to attack warning and movement in_ response to detection Minimum Speed requirements depend on available time vehlcle hardness and threat Some typical speed requirements gate illustrated in Table 8 against threats by optimally heavy ICTs baSed on in-f11ght retargeting of'RVs are shorter than typical attack warning tlmes there is only one effective mobility Ja Emode against such threat3 a very high dash speed to escape aimed attacks I u wu-th - - 1'm 92 Table 8 MINIMUM TL VEHI CLE SPEEDS N MTIHR T0 OUTRUN A PATTERN BARRAGE BY HEAVY SOVIET ICBMs U 7 RVs 2 3 MT TL VehiCle Hardness IICT or WT 1 min 2 psi 10 ps1 25 psi 'BUTMinTnum-TCT withoht __01in fligh1 retargetinglsugosi1bletW$s for '100 6 Possible ICTs with 250 87 47 i 3 inrflight retargeting 500 V174 94 U Dash systems are normally parked ready for one time dash-i '0n-attack'warning The movement frequency in response to detection 1 depends on_both TOT and the detection frequency for example the 'ooverage frequency of satellite surveillance syStems Both movements can be forced toward continuous mobility if both ICT and detection intervals decreases 774 4-- 39 About 80 000 mi2 or 21 percent of the total land area in CONUS is federally Owned Some 65 000 to 100 000 mi2 of this pdblic domain may be suitable for offroad operations in the western United States Other possibilities are deployments restricted to military bases possibly including contiguous land from the Bureau Of Land Management To illustrate force survivability possible in these deployment areas Table 9 shows the attack throw weight needed as a function of missile vehicle hardness to barrage the areas for 100'percent kill Table 9 ATTACK THROW WEIGHT NEEDED TO BARRAGE DEPLOYMENT AREAS FOR 100 PERCENT KILL U Throw Weight Mlb Deployment Area - TL Hardness psi Size Type n 11 12 2 10 15 25 Military reservations 10 000 0 07 0 57 0 86 2 0 000 contiguous ELM 22 000 0 16 1 3 1 9 4 4 DOD public domain 65 000 0 46 3 7 5 6 13 0 985_ As is seen in Tables 8 and 9 offroad ICBM systems must be relatively fast in order to escape aimed attacks and relatively hardd in order to minimize deployment area requirements for barrage attacks The practical hardness limit of wheeled offroad TLs is 10 to 25 psi E For deployment such systems would need all the public domain poten i tially available Their speed requirements can be met for threats 5 -based on ICTs Without in flight retargeting and possibly for dash on tattack warning However they would be unable to escape threats based on ICTs with inrflight retargeting of RVs While speed could be in acreased by air-cushion heavy lift helicopters or VTOL type vehicles these vehicles are softer and may need more deployment area than is potentially available slia CU ICBM systems would use large payload long-endurance aircraft as mobile ICBM b ases in one or more oper ationa1 modes U Continuous Airborne Alert Airborne alert generates an area target with Superior survivabi1ity under blind barrage attacks Since routine peacetime operations over CONUS are believed to be precluded because of public safety deployment 1s usually assumed to be over international waters supported from a few large coasta1 bases While 1pattern barrag1ng does not appear threatening b ecause of the large- available patrol areas aircraft 1o1tering over international waters 9may be exposed to a variety of as yet illedefined technical threats 7 40f detection tracking and subsequent negation U -Dispersed Grannd Alert - Aircraft would be deplOyed with 5 missiles and crews cuboard ready to scramble upon attack Warning Sur 'vivability is similar to that of a bomber tanker force with depressed ftrajectory being seen as the main threat survivability depends ion aircraft reaction time escape Speed base location and has 1ng density Collocation with the bomber force on existing baSes is likely to intensify the bomber Survivability problem so additional bases may be required U Mixed Mode-w Airborne and strip alert modes can be combined fin a mixed mode where the force proportion would vary with the defence icondition Defcon level One concept would set cr ew ratios and mainte gnance faci lities at a level permitting full airb orne alert operations over a protracted crisis of s_everal months gif The survivability of airhmobile systems depends on their 1deployment mode and on the quality and confidence o both strategic and tactical warning In essence survivability againSt surprise attacks demands continuous airborne alert If s trategic warning can Jbe assured a mixed mode with cont innous airborne alert can he need during a crisis It tactical_ attack warning can be assured a strip mode can be used provided the system has a reliable and compatible reaction and escape capability In theory reliable- attack warning 'with or without strategic warning should lead to equal survivability Mewever since the aircraft reaction time needed for safe escape is on v e715 the order of 2 min it probably cannot be maintained routinely without strategic warning The system cests of course increase frOm strip Ealert to airborne alert airborne alert may also have problems with fuel consumption U Independent of their deployment mode airemobile systems have limited postattack endurance aloft and must rely on a soft targetable base structure for extended endurance a problem shared with the bomber force One proposed means for enduring survival is the use of large numbers of emergency dispersal sites for aircraft support and turn- around U Concealment Area Target ystems While overt area systems grely on mobility and speed for survival another alternative is to deny timely and useful targeting information to-the attacker The critical requirement then is to prevent detection with short ICTs rather than 'to outrun an attack Submersible launchers are readily concealed in_ -water but concealment is more difficult in other media 92 IDeep underground basing discussed under Point Targets on p 65 can be converted to an area target by the use of concealed launch exits Concealed launch exits would terminate some distance below the ground surface can be constructed from below without any observable3 'signs or activity on the ground surface and could be opened by an i explosive system to permit missile launch in about an hour g9 Concealed exits would provide a hard area target inherently -the best of target geometries Moreover the cost of underground bases jusing concealed exits may be less than that of other basing Once bdilt however the exits depend critically on measures to maintain location security throughout the life of the installation While secrecy may appear a cheap and attractive way of gaining survivability it is also risky one because one can never be confident of his secret This vul notability could be alleviated by providing a capability for reopening damaged exits or excavating new ones With such a back up launch capability might be restored in a few days or weeks 7 'm mw WM ww U Submersible barge systems combining concealed area mobility and hardness have been proposed as a low cost alternative to FEM sub Tmarines Deployment has been postulated in U S inland or coastal 221 waters that can be essentially closed to enemy antisubmarine-ner are E'removing the need for Quiet submarines of h1gh speed and maneuvers lbility The launch vehicle can be a relatively inexpensine submarine with reduced requ1rements for manning speed power operating deth and navigation and communication equipment Possible deployment areas include the Great Lakes Hudson Bay Gulf of Maxico the Alexander Archipelago off Alaska and the coastal waters a1ong the East and West LCoasts Summary Observations 1 w 1 L9f This review of the poss1ble ICBM -basing concepts does not 1ndicate any perfect system Some consepts face potent1al problems Ifrom sate111te surveillance which might eventually provide near reels time detection and tracking of overt mobile vehicles others pose aproblems with the public interfaces they would generate The more jlikely-candidates at this time are-shellsgame _cealed hard line and submerged barge systems These eys items can all deploy virtually identical missiles Delivery accuracies ava11ab111t1es and reliabilities may differ but not markedly Larger 'E d1fferences appear in postattack endurance and force responsiveness i EMajor differences may also arise in SALT verification o f forces 125' Any choice among the new basing opt10ns of course will be Egreatly affected by costs The general cost-effectiveness trends of Eshell game and hard line systems show that hard line systems are rela Etively more effective against smalls-r CEPs but any final cost compari- Eson will depend on the unit Shelter and line Costs The cost of deep underground Bases- is mostly associated with the exit systems Anstere basing in Submersihle barges or cheap submarines would seem to 1 offer a clear cost advantagerver ongoing development Of sea-based sys tems The cost of air mobile systems can vary widely depend'in g on the operational mode Selected Whatever detailed cost comparisons may SALT considerations include a unilateral statement by the S Delegation that t_he 3 would consider the deployment of oper- -at ional land mobile ICBM launchers durin g the period of the Interim Agreement as 1ncons1stent with the Obj Cth of that - e78uw reveal abqut the choice of new basing options it is very clear that rebasing for the purpose of enhancing the survivability of the ICBM force will be costly UNCLASSIFIED - 1- Iv 'The foregoing perspective of current issues and future options for the U ICBM force is intended as an objective background for decisionr making How that background is assessed as foreshadowing the future _o'f the force depends upon some further subjective considerations What are the crucial isSues What views are taken on those issues Which of the available options are responsive to those views2 Answers to these questions are not necessarily singular they may vary with people and time While preparing this perspective the authors have formed their own judgments on the answers In this final sectiOn 3 We depart from the summary perspective and present our views and j-udg ments on what all of this implies for the future of the U S ICBM force Thus this final assessment forms a separate more subjective part of _the report rather than presenting th conclusions of a quantitative analysis Our readers may represent a Variety of ViewPoints they are encouraged to draw their own conclusions We see the most important and pervasive concern to be the preSer- elvation of the longmterm capability of ICBMs to deter a preemptive nuclear attack both in fact and in appearance in the face of the fore- seeable developing threat The principal source of this concern is the large scale Soviet deployment of accurate missiles that could threaten the survival of U S silos I Averting that possibility by negotiated limitations on MIRVs or throw weights is to suggest that SALT determines the future of the U S ICBM force Avoiding the consequences of the threat either by abandon ing the silos or rehasing the implies that a silo-based missile force should do without To ignore the concern is to deny both the scenario and -rationale for strategic nuclear forces While these futures are extremes which may bound the future of U S ICBMs We find them neither attractive nor realistic as solutions UNCLASSIFIED UNCLASSIFIED -80- THE PIVOTAL ISSUE Instead of boundary solutions we have sought the pivotal issue that more than any other might be a watershed for the future of the force we submit that such a pivotal isSue is whether each of the 7 strategic offensive forces ICBMs bombers or some un que role within the U S strategic posture If the are considered simply as one of three different ways of doing the same job then we' are not sanguine about their prospects as key elements of the future ULS strategic posture However if the ICBMs are seen to have a special role in the posture because of their unique capabilities and characteristics then several interesting alternative futures are I evident to us Resolution of this pivotal issue hinges not only on the actual 3 characteristics and capabilities of ICBMs and on their actual role in the Strategic posture but also in large measure an public perceptions of the job that ICBMs are supposed to do To suggest how decisive this issue may be we offer below two very different prOSpects for the future of the force depending upon how the question is resolved A FUTURE WITHOUT MUCH PROMISE If the U S ICBM force is viewed as just one of three strategic offensive forces whose principal and common role is to deter a nuclear attack through assured retaliation then the overriding concern will continue to be the survival of ICBMs in a preemptive attack Compar isons among the three forces on the basis of survivability are invited simply because it is the basic common denominator of retaliatory capa- bilities Other qualities admirable or not are likely to be dis counted as not essential or central to the principal role of strategic forces The most responsive options for significantly improving the sur vivability of the ICBM force to a disarming attack are to launch the force on attack assessment or 2 to rebaSe the force While there are other alternatives they appear less effective or practital For example proposals to make the survivors more capable such as UNCLASSIFIED UNCLASSIFIED 81 deploying larger missiles or more-RVs pet missile will generally not be recognized as solutions because the dominant perceived concern is force survivability -not the ability to execute some wellndefined task -requiring so much throw weight or $0 many RVs Farther hardening of silos looks like a lOSing game in the face of increased missile accuracies Active ABM defenSe may be a techni4 cally effective way to improve the-prelaunch survivability of the ICEM force but its acceptance is impeded by the restraints of the ABM Treaty and the emotional legacy of the ABM debates I Lau Ching the ICBM force an attack assessment iS-Qrobably the simplest and most costeeffective way-to frustrate a counterforce attack I But as a declared policy we believe it would be vigorously opposed as both dangerous and unstable an accident could theoretically precipitate a nuclear war 5 Nevertheless we believe that the technical capabilities to launch ICBMs on attack assessment should be developed their daf rrenca valuer so that no adversary would dare assume that the U S could not launch the erce out from under anYattempted disarming attack They should not be costly we also_see technical capabilities as pro viding additional flexibility in crises where the declaration of an 1 emergency readiness to launCh the force on_attack assessment could serve as an additional rung in an escalation ladderurge that the surwivability of ICBMS be predicated on a policy of launching the force on attack assessment the assurance of ICBM retaliatory capabilities should not rest upon such an aweSome commitment The possibilities for improving the prelaunch survivability of 3 ICBMS through rebasing are-numerous but we have seen none that look promising as a solution for the entire force Our appreciation of the rebasing concepts now being considered for the U S ICBM force leads us to believe that if applied to the entire ferce they would be vefy costly of debatable effectiveness and likely to sacrifice some imr portant attributes accuracy and security of the present forc e Of coarse the rebasing concepts continues but a good single Solution is not yet in sight UNCLASSIFIED UNCLASSIFIED -32- Diversified basing of the ICBM force has been proposed as a means to diversify vulnerabilities but it will impose most of the same draw backs as a single rebasing solution it will be costly there will be arguments over the relative effectiveness of the several basing schemes and some of the better characteristics of the present silo basing are likely to be lost Diversified basing concepts will result in a frag- mented ICBM force and if adopted primarily to improve the overall force - survivability each fraction will inevitably be subject to survivability comparisons The failure of some portions of the ICBM force to measure up to the perceived survival standards of would result in pressures to eliminate marginal or inferior fragments Hence piece meal dismemberment of the ICBM force might be facilitated In sum if the ICBMs have no unique role within the U S strategic posture we do not see a promising future for them Their evolution A would then hinge upon overall force survivabilitz and we have not been able to identify any good forcerwide options forgr lieving present con cerns over ICBM survivability against a preemptive counterforce attack SEVERAL PROMISING FUTURES If it is accepted that each of the strategic offensive force ele ments could have a special role or roles within the U S strategic poSture then we see several interesting alternatives for the ICBM force We can think of at least four Special roles for perhaps a there are more Limited Strategic Operations While providing L30 capabilities cannot be claimed as the exclusive domain of ICBMs we believe that ICBMs possess and promise more of the desired attributes for LSOs than any other strategic force element If LSOs are a Special role for ICBMs the principal concerns will be to ensure effective and flexible targeting with minimum collateral damage Even though these cencerns seem exaggerated to us We belieVe they reflect a preoccupation with a narrow definition of the purpose of strategic forces with extreme thrEats and with simple analytics UNCLASSIFIED UNCLASSIFIED 133 The prospects for controlling onwanted collateral damage while achieving the desired level 0f target damage are dominated by delivery accuracy There is little doubt that the accuracy of ballistic mis Silas can be improved markedlY'with the technical means available the questions have to do with Whether we should improve ICBM accuracies 9 because of their how much and by what means a The highest possible weapon delivery precision should be sought- for LSD capabilities For some L50 tasks zero CE via terminal homing Eis desirable so that the smallest pOSSible yield or even conventionsl explosives can be employed Where conditions dictate or permit While zlreliance_on terminal or external navigation aids fer sesured retaliatory capabilities-might be eschewed we see no reason Why their benefits I for lesser contingencies should he orsworn we belieVE-that ICBMs should not be restricted to ell inertial guidance This imposes an unnecessary limit on delivery accuracy and hence upon the required weapon size and consequent collateral damage OptiOns for improving the targeting flexibility of 163MB for L805 include additional C3 function's BXplic it targeting variable yield selectable Weapons etc All seem worth- while -at least in small quantities None seem very eoStly compared to new missile or rehasing the ICBM force the greatest impediw 3 ment to their development is that they are not largesscale forcedwide aprogram Options a I Large numbers of ICBMS are not required for LSOs nor are larger missile5'with heavier throw weights In some cases MIRVS are liabil ities rather than assets In the present ICBM force our mos I accurate missiles are and that eculd be awkward for some LSOS A few very accurate single RV missiles should be available Sines large numbers of missiles are not required for'LSOS we be- lieve that elite fbrce concepts are attractive Some of the-features desired for LSOs could detract from the performance of other strategic 5 tasks if implemented throughout the ICBM forCe Moreover high confidence hard-target kill capabilities for LSOS against selected jhardened facilities would not engender as much concern about their UNCLASSIFIED UNCLASSIFIED Counterforce potential if they were acquired only in limited numbersr for an elite force - An elite ICBM force for LSOs might consist of a squadron 50 or a wing 150 of Minuteman missiles If the elite force were seen as presenting a preferential target for a Soviet LSO it might be deployed ianing VI at Grand Forks under the Safeguard ABM umbrella That arrangement might also be seen as advantageous in the rationale for 1 maintaining a single Safeguard site it could shift the principal threat scenario from an all-out attack to 1305 a threat that may be technically less demanding or overwhelming If we have any reservation about the potential future of the ICBMs for a special role in providing LSO capabilities within the U S stra- tegic posture it is not with the qualities of ICBMs but with the con cept of LSOs It remains to be shown Whether LSOs are a durable and useful concept contributing to deterrence If they are we think ICBMs will evolve as a principal instrument of that concept Assured Reserve Capabilities Another special role is that of providing a reserve of strategic nuclear weapons that can be held inviolable and available for a long time in general nuclear war While the abilities of U S stra tegic offensive forces to survive in the transattack period have been widely analyzed and discussed far less attention has been given to the long-term survival of strategic forces in a seriously degraded postattack environment Because of their relative autonomy during ex- tended patrol operations nuclear-powered submarines offer attractive survival characteristics with the possible exception of assured two way command communications for periods of several months into a post- attack period Beyond that time the breakdown of logistic support would probably limit the availability of We believe that the U18 ICBM force has several shortcomings for both immediate and long-term postattack survivability The immediate survivability problem past the first day is tied up with providing electrical power while the long term prob1em in the following weeks is the same as for the logistic suppert Both of these- UNCLASSIFIED UNCLASSIFIED n85n problems could be favorably affected by making the missiles dormant 1 we belieVe that dormant operation of a-portion of the Minuteman ICBMS would provide a lowecost reserve force with longrterm survivability at least until a significant Soviet counterforce capability emerges In the more remote future if Soviet counterforce capabilities dominate the question of ICBM Survival into the pestattack period - rebasing of 103MB for an assured reserve force may be an attractive option One concept worth exPloring is the basing of dormant missiles in secure underground bases The needed size at such a reServe is probably no more than a 3 hundred megatons deliverable to several hundred separate aimpoints The use of missiles would reduce the resuired number of delivery i vehicles but they might be less manageable than a larger number of small missiles with single warheads In any event we do not see wh reserve force missiles should be burdened with the features and costs for quick reaction high accuracy or sophisticated defeuse penetration are certainly candidates for an assured reserve force In a competition landwbased ICBMs may have two advantages First and _Qerhaps meet important ICBMS in underground bases are likely to be cheaper to store securely out of harm s way than continuously at sea Second ICBMs can probably be stored and controlled consider- ably longer than the-operational life of without land based logistic support Counterforce If a special role for ICBMs is'to provide counterforce capabilities I we see an interesting but very controversial future Any investment at counterforce capabilities in the 103MB will be seen by many as de stabilizing unless they are rebased to better survive any foreseeable Soviet attack 0n the other hand even if the more securely based some would challenge the need for substantial counterfOrce cana - bilities unless the 0 8 had aspirations toward a disarming first strike posture Either way any attempt to deVelop a significant chunterforce capability in_the U483 strategic posture is a journey on a bumpy road UNCLASSIFIED UNCLASSIFIED 86 we are aware of_some sophisticated arguments for acquiring or threaten ing to acquire counterforce capabilities but we do not think they would carry the day in the present public debate The technical routes to substantial counterforce capabilities in clude improvements in hard target kill capabilities through increased accuracies and yields or through a larger missile with greater throw weight There is little doubt of the technical feasibility of either approach If constrained to the present missile the most expeditious route might be to augment the inertial guidance with radio aids With a larger missile larger yields and greater numbers of RVs could come pensate for the accuracy limitations of alldinertial guidanCe If ICBMs are rebased to make them relatively immune to attack then the need for counterforce improvements beyond those needed for LSOs is hard to justify Moreover if the requirements for counter- force hard-target kill capabilities do not exceed those needed fur LSOs the qualities of the present fixed silo basing for LSOs seem preferable to those of most rebasing concepts If counterforce capabilities well beyond those required for LSOs are somehow justified then for a crisis stable posture the adopted basing scheme would have to enforce an un favorable exchange upon the attacker in terms of counterforce capabil- ities expended versus those destroyed Some of the basing options for a new ICBM now being studied by the Air Force meet that criterion but so do sea basing Options The possibility of investing any counterforce capabilities in rather than in land based ICBMs cannot be discounted if the dew velopment of substantial hardetarget kill capabilities is deliberately undertaken by the U S With external guidance aids we believe that the accuracy of can be adequate for hard target kill capabilities within the Trident missile throw weights Thus ICBMs might have to compete with for any special counterforce role in the U S stra tegic posture We are not sanguine about the competitiveness of the available re- basing options for ICBMs They are not clearly superior to the in survivability even though they are different in their vulnerabi1 ities The new basing options are likely to be much more costly than UNCLASSIFIED UNCLASSIFIED 87r the present silo basing possibly as costly as submarine basing Howe ever if the desired or reQHired connterforce capabilities could be I efficiently packaged in a relatively small number of missileSr say one Or two hundred then the cost of the rebased force would be bounded in proportion A numerically small force would likely-reguire a large missile with many accurate MIRVS and such a missile may not be com- patible With mobile basing concepts that have been propdsed Eguivalence The concept and precepts of strategic equivalence presently re J fleet some concerns about Strategic posture asymmetries and_thirdeparty uperceptionsru Ehese indicate a special role for ICBMs in the stiam tegic posture because ICBMS are an important part of the Soviet posters If the U S wants ICBMS in its strategic force posture so as toi 1 look equivalent to the SOViets then retention of the existing force which is paid for and relatively inexPensive to maintain is an attrac- tive option 'GiVen only the'political imperatiVEs of matching the Soviets in possession of ICBms and in aggregate numbers of strategiC delivery vehicles there is no more cost effective choice than the present Minnteman force A If the measures of equivalence'become more sophisticated and in clude compariSons of ICBM throw weight numbers of accuracy etc silo basing will continue to offer cost-effective options for maintain ing eouinalence i Refitting the present silos with atlarget missile k - while not cheap will almost certainly be cheaper than most other means for inereasing ballistic missile-throw weight Thus the present silo based ICBM force could continue to be an inexpensive way to maintain equivalence with the soViet strategic pos ture Whether the rationale for equivalence is sufficiently developed and accepted to secure a special role for ICBMs is prohlematical If 'the concerns for the survivability and stability of ICEMs-lead to tee basing then we doubt that the ICBM will continue to Enjoy its present substantial cost advantage over other strategic offensive forces In any event we believe that the political climate will faVQr equivalence over stability and that the economic climate will continue to favor the present silo-based ICBMs over missiles otherwise based UNCLASSIFIED UNCLASSIFIED 3887 THE OUTLOOK We believe there are at least four interesting and unique roles for ICBMS within the U S strategic force posture The first and clearest is specialized capabilitiea for L303 provided by improvements in a portion of the present ICBM force The second is a costeeffective strategic reserve force achieved by dormancy of a portion of the pres- ent missiles This Should suffice at least until the Soviets possess a significant hard target kill capability after that any strategic reserve force will require more secure basing than will be afforded by our present ICBM silos The third role for ICBMs is that of a limited force with durable high-quality counterforce capability This role is clouded by lasting 3 concerns about stability and disarming pestures and by potential competition from Effectiveness in this role does not depend on hard target kill capability rather it depends on a cost effective and competitive basing scheme that is relatively immune to I attach We have not recognized such a scheme yet The fourth role is that of-providing ICBM equivalence at low coat The key here is to retain as much as possible of the present silo bas - ing other basing schemes surrender- the substantial cost advantages of ICBMs over and bombers we believe that these special roles for ICBMs pose interesting and attractive future alternatives for the U S ICBM force especially when contrasted with the future we see if the ICBMs are denied any special role within the U S strategic posture we have seen no new basing option for ICBMs that would cure their shortcomings without also sacri ficing some of their best characteristics While the search for bas- ing options should proceed of course we are perSuaded that the future of the U S ICBM force should not be predicated- inadvertently or in- tentionally- on finding a single new basing scheme It might just cost us the entire force and we think the U S strategic posture would be much the worse for the loss 1 UNCLASSIFIED This document is from the holdings of The National Security Archive Suite 701 Gelman Library The George Washington University 2130 H Street NW Washington D C 20037 Phone 202 994-7000 Fax 202 994-7005 nsarchiv@gwu edu