How the Strategic Air Command Would Go to Nuclear War

Commander-in-Chief Strategic Air Command General Thomas S. Power (l), seen here with Air Force Research and Development Commander Lieutenant General Bernard A. Schriever (r).  Power was CINCSAC when the EWO Checklist was in force for the 55th SRW. (Photo in author’s collection)

Declassification of Red Dot "Emergency War Orders" from 1964 Opens Window into Strategic Operations

SAC's Role in DEFCON System Detailed

Bruce Blair on How the Strategic Air Command Would Have Gone to Nuclear War in the 1970s - update

Washington, D.C., March 13, 2019 - Last month’s posting by Robert S. Hopkins on “How the Strategic Air Command Would Have Gone to Nuclear War” provided incredible detail on SAC procedures during the 1960s. Strategic Air Command veteran Bruce Blair takes the story in to the 1970s, with an extraordinary account, based on personal experience, of how SAC would have carried out its nuclear mission if deterrence failed.

Blair’s account explains how the Emergency War Orders system had changed by the 1970s, with Red Dot messages used for executing Armageddon-scale nuclear strikes on the Soviet Union and its allies, or on China. He also shows how launch-on-warning had become part of the training routine at SAC: “we trained extensively to launch promptly on warning of incoming Soviet warheads and thus avoid the destruction of Minuteman (and Titan) missiles on the ground or in the first few minutes of flight.”

 

Original posting:

Washington D.C., February 25, 2019 - A recently declassified Strategic Air Command (SAC) checklist sheds brand new light on the procedures that SAC would have followed in the mid-1960s if U.S. nuclear forces had gone to war. The National Security Archive at George Washington University is today posting this intriguing document for the first time.

The checklist provides the first fully declassified details of SAC procedures under Defense Readiness Conditions (DEFCON), from 1 to 5, along with the Emergency War Order red dot messages that would have directed SAC bombers and missiles to launch nuclear strikes against the Soviet Union and other targeted adversaries.

Independent scholar Robert S. Hopkins III obtained the new material through research in recently declassified U.S. Air Force records. He kindly provided the documentation, introduction, and document descriptions for this posting.

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How the Strategic Air Command Would Go to Nuclear War

by Robert S. Hopkins, III

 During the Cold War the Strategic Air Command (SAC) kept its bomber and missile forces at high alert, with strategic bombers adjacent to runways slated for rapid launch.  In event of a crisis or a sudden outbreak of general war or even a decision for a preemptive attack, SAC’s bomber, tanker, and missile forces could respond with varying degrees of preparedness. SAC’s readiness for war was defined by the Defense Readiness Condition (DEFCONs) and the Emergency War Order (EWO) directed by the National Command Authority (NCA), the president and the secretary of defense. Yet tight secrecy controls shrouded the mechanics of these processes while the cryptological nature of the actual launch and execution messages made them inaccessible.[1] A recently declassified SAC combat wing checklist from 1964 published today by the National Security Archive for the first time discloses specific SAC actions at each DEFCON level as well as the Emergency War Orders used to direct the launch and execution process of SAC’s highly orchestrated alert force.

The checklist was used in September 1964 by the 55th Strategic Reconnaissance Wing (SRW) at Forbes AFB, KS. The 55th SRW controlled two squadrons of Boeing RB-47 electronic intelligence (ELINT) aircraft and one squadron of Convair SM-65E Atlas intercontinental ballistic missiles (ICBM).[2] The RB-47s were used for one of the wing’s primary missions: aerial reconnaissance.[3] As part of its EWO commitments, the 55th SRW distributed a secret checklist “so individuals directly associated with EWO launch of aircraft and missiles will readily understand their tasks.” The checklist included, inter alia, an EWO synopsis, EWO messages, DEFCON summaries, and Command Post functions, as well as aircraft and crew disposition and EWO mission assignments. These were specified by the Single Integrated Operations Plan (SIOP), the Joint Chiefs of Staff plan for nuclear war, in this instance SIOP-64 Revision 2.

EWO checklists such as the one used by the 55th SRW facilitated the timely management of SAC’s ongoing ground and airborne alert programs that improved its war readiness. SAC began evaluating quick-response ground alert in October 1955, but the Joint Chiefs of Staff (JCS) deferred any action until July 1957 with the establishment of ground alert for B-47s at bases in the United Kingdom. This expanded to include ground alert in the U.S. of both bombers and tankers by 1960, with the goal of having 30 percent (later 50 percent) of its aircraft able to launch within 30 minutes of notification, which dropped to 15 minutes with the introduction of Soviet ballistic missiles. Airborne alert tests began in January 1958 using B-36s, and by 1959 included B-52s. The Chrome Dome airborne alert program was approved on 6 November 1961 and ended after the crash of a nuclear-bomb-laden B-52 near Thule, Greenland, in January 1968.[4] In either case, bombers were launched under “positive control”, which meant they were authorized only to take off and fly to their positive control checkpoint (their “failsafe” point) where they would orbit until they received an execution message issued by the JCS.

 

Emergency War Order Synopsis

To ensure that all US forces operated on a common timetable, the JCS established several key “hours” associated with the EWO and SIOP. H-hour served as the absolute start time for all operations. Designated by the JCS or by SAC’s Commander-in-Chief (CINCSAC), depending on the circumstances, “A” hour referred to the beginning of the generation of forces to raise their alert level. The Joint Chiefs could also designate an “E” hour (later Execution Reference Time—ERT) indicating the execution time of the SIOP strike force.  “L” hour, not mentioned in the checklist, was the reference time used for the Positive Control Launch of any components of the SAC aircraft alert force; it also established DEFCON 1 and the “A” hour for SAC.

In the event an “A” hour was declared, the 55th SRW would deploy 11 RB-47Hs to Whiteman AFB, MO, in preparation for their EWO mission. As the RB-47s were configured primarily for ELINT collection their chief mission would be to detect the operational electronic signatures of hostile forces. With the declaration of an “E” hour, dispersal would halt and the RB-47s would launch from Forbes or their dispersal base at Whiteman. Once executed and launched, three of these would “reconnoiter the Far East and Post-Strike in Japan” while the remaining eight airplanes would “reconnoiter the European Area and Post-Strike in Europe and the United Kingdom.” Their immediate goal was to meet their Air Refueling Control Time (ARCT) when an air tanker would be at hand to refuel the RB-47s en route to their EWO deployment areas in Europe and Japan. Meanwhile, the 548th Strategic Missile Squadron (SMS) would launch nine Atlas Es to their targets. By early 1965 the Atlases would be retired, rendered obsolete by the quick-launch Minutemen.

 

Emergency War Order Messages

Perhaps the most significant part of the checklist is the recap of EWO messages. There are two categories: EWO Index and EWO Preparation Index. The former, known as Red Dot messages, were for use when war was imminent or underway.  They authorized the launch and execution of SAC forces on their EWO routes, where, depending on instructions provided by Emergency Action Messages from the NCA, they would implement one of the options provided by the SIOP. The latter, the Blue Dot messages, covered arrangements that preceded the execution of EWOs, such as DEFCON levels, reaction postures, and command arrangements.

No doubt their specific applications evolved over time, but the implementation of these messages was quite straightforward and applied to all SAC forces, including B-47, B-52, and B-58 bombers, KC-97 and KC-135 tankers, EB-47L and KC-135A/B airborne command posts, and Atlas, Titan, and Minuteman ICBMs. For example, a B-52 crew responding to an alert klaxon would decode the message broadcast over the base’s command post radio frequency while starting the aircraft’s engines. The decoded message might be a preparatory alert notification Blue Dot AA7 “Minimum Reaction Posture, Aircraft”. The bomber’s engines would be shut down and the crew remained in the aircraft ready to launch with minimal delay. Other Blue Dot messages notified crews of a change in the DEFCON, the dispersal and recovery of the B-47 alert force, or a change involving the CINCSAC provided for by pre-delegation arrangements.[5]

A Red Dot 1 message directed the positive control (PC) launch of all Alfa Force airplanes on daily alert. This directed the bombers to their positive control point.  Assuming that the Alfa Force had already launched, a Red Dot 2 message launched the recently generated Charlie Force. In the event of a mass simultaneous launch of all SAC bombers and tankers (Herman Kahn’s “wargasm”), the Red Dot 3 message launched the Alfa alert bombers, the Charlie generated airplanes, and the “Foxtrot force,” the last group of bombers and tankers to go on alert. In SAC planning, the “Foxtrot force” had the function of a reserve force that could be used in retaliatory missions.[6]

In all cases the Red Dot positive control messages restricted the bombers to proceed only to their positive control point, Once the NCA decided to proceed with nuclear attacks on targets specified in each bombers’ combat mission folder (CMF), SAC would broadcast a Red Dot 4 message to execute their mission, and the bombers would then continue to their targets.

In the event of gradual escalation, bombers reached and orbited at their PC points in the expectation that their highly visible presence would convince the Soviet leadership of U.S. resolve, ending the crisis. Should this fail, a Red Dot 4 “execution order” would then be transmitted to launch SAC’s ICBMs and release the bombers from their PC points to their targets. Presumably the Red Dot 4 message could be used in the event of a “bolt from the blue” scenario, ordering the immediate launch of ICBMs and all alert and non-alert forces that were available for launching. In this event the bombers proceeded directly to their targets without pausing at their PC point or requiring an additional execution message. Red Dot 6 may have been a placeholder reserved for an unspecified contingency plan. Red Dot 7, “Strike Execution Big Jump,” may have been a terminate order.

 

DEFCON

The Checklist provides the first full declassification of SAC operations at various DEFCON levels.  The airborne and ground alert operations discussed earlier were keyed into the DEFCONS, which corresponded to different levels of international tension. The lowest is DEFCON 5, which reflects “normal peacetime conditions.” For many years SAC maintained its forces at DEFCON 4, which included enhanced intelligence activities, security alertness, and a greater degree of preparedness in the event the DEFCON increased. At DEFCON 3 (seen during the 1973 Arab-Israeli War in response to potential Soviet intervention) the battle staff at each SAC base would assemble and prepare dispersal plans for implementation. Base security was heightened and flying operations were restricted to a four-hour radius from the base. ICBMs not on alert or undergoing maintenance would be generated and placed on alert using a 24-hour work schedule. The airborne component of the Post Attack Command and Control System (PACCS), including the Looking Glass airborne command post and radio relay aircraft, would be launched.[7]

DEFCON 2 required the “immediate generation of the SAC force,” putting all forces, bombers, and ICBMs on high alert. All personnel would return from leave and all crews for “first cycle aircraft”—those launched in the first wave of an attack—were restricted to base. Except for airborne alert missions underway, airborne command post operations, and test aircraft, all flying would stop so that the bomber force could be readied for use. Moreover, officers would distribute Combat Mission Folders (stipulating routes and targets) to crews to permit briefings and folder review.  

The DEFCON 2 status of ICBMs was also complex. The ICBM force of Atlas and Minuteman missiles was undergoing development, with some missiles under the control of the Air Force Systems Command (AFSC), which was responsible for testing and deployment of Air Force weapons.  Under an AFSC-SAC Emergency Combat Capability (ECC) agreement, AFSC gave SAC temporary operational control of all AFSC missiles at Vandenberg AFB, CA, and Cape Canaveral AFS, FL, that could be configured with nuclear warheads and launched.[8] Under DEFCON 2, missile launch crews would go in the “MINIMIZE” posture eliminating all non-essential communications and restricting missile control sites to crews only. Moreover, launch crews prepared themselves to go to the next level of readiness.

During the 1962 Cuban Missile Crisis, SAC was at DEFCON 2. All non-critical flying ceased and aircraft undergoing maintenance were made sufficiently flyable to carry out an EWO strike. SAC readied for launch 1,436 bombers and 145 missiles and maintained a “continuous stream” of B-52 bombers on airborne alert, 65 in the air at any given time, ready to fly to their targets.[9]

Should U.S. forces move to DEFCON 1, SAC would take steps preparing for the NCA’s execution order.  Bomber and tanker crews would report to their aircraft, start engines, and receive a Blue Dot AA6 message indicating the change in DEFCON. Crews would then shut down the engines and remain in their airplanes. As the EWO checklist noted, “Each SAC Commander must prepare his aircraft and crews for launch as rapidly as possible and must be prepared to maintain them in ‘cocked’ configuration within the limitations imposed by the readiness condition order for an indefinite period of time.” ICBM crews would take their assigned positions at launch control center consoles and personnel would stay in the centers as long as missiles were in “alert configurations.”  Power generators used for launching missiles would go on-line. SAC also had a DEFCON 1M level which stipulated that “ICBMs will be counted down to point of minimum hold,” meaning that they were ready for instant launch.

As the SIOP and the related EWOs evolved in complexity during the 1970s and 1980s, EAMs struggled to remain simple enough to avoid ambiguity and the risk of misapplication by crews. Specific JCS messages tied to specific Major Attack Options (MAO) and Selected Attack Options (SAO) replaced the Red Dot messages. SAC messages replaced the Blue Dot messages, with specific SAC actions for each message built into bomber/tanker CMFs. Missiles were a separate case.

Note: The author wishes to acknowledge the efforts of George Cully in acquiring this document, and comments by William Burr and David Rosenberg.

 

The Documents

update

How SAC Would Have Gone to Nuclear War
in the 1970s

by Bruce Blair

Robert Hopkins has done a public service by unearthing and publishing the 55th Strategic Wing EWO Checklist for 1964. The document and the commentary are illuminating and brought to mind my experience with SAC nuclear operations during the following decade.

In the early 1970s, when I served as a support officer for the SAC Airborne Command Post ("Looking Glass") and then as a Minuteman II ICBM missile launch officer, the basic procedures (Emergency War Orders) outlined in the 55th SRW “Checklist” for 1964 remained the same, but the message flag words of the Emergency Action Messages (EAMs) used to generate and execute the missions of strategic bomber and reconnaissance aircraft, Minuteman missiles, and ballistic missile submarines (SSBNs) had changed in fundamental ways.

A Red Dot 1 message would not have been used to change the alert posture of U.S. strategic forces. By 1970 it instead would have ordered the strategic forces to carry out their wartime missions – in other words, execute the Single Integrated Operational Plan (SIOP). This always required presidential authorization, either his personal approval in the immediate circumstances or that of his authorized surrogate. Although the legal chain of command for presidential succession ran through the Vice President, senior Congressional leaders and then the Cabinet secretaries in the order of the creation of their departments, the nuclear chain of command would likely have quickly bypassed civilian successors and rolled over to senior military commanders vested with pre-delegated launch authority. Every president from Eisenhower through Reagan had pre-delegated this authority to a raft of these commanders in order to ensure rapid execution in the event of decapitation or communications outages that prevented the president from personally authorizing a nuclear strike.

It was thus arranged that the Red Dot 1 message authorizing SIOP execution used a Sealed Authenticator System code that no civilian including the president possessed. SAS codes were held and distributed by the military, especially the command-control facilities that supported senior military commanders with pre-delegated presidential authority and the executing commanders at the bottom of the chain of command (the bomber, submarine and Minuteman/Titan crews).

Red Dot 1 options were designated by a specific war plan number (e.g. '55') in the EAM, which also designated a 'E' hour, otherwise called the Execution Reference Time (ERT). For example, war plan '55' might have called for the execution of a major SIOP option that unleashed the full might of the U.S. strategic forces assigned to attack Soviet nuclear forces (a counterforce strike), but withheld nuclear strikes against cities. (We learned in the mid-1980s that SAC planners had designed the counterforce targeting in such a way that all the major Soviet cities would have been obliterated.) The ERT ensured that all U.S. forces carried out their strikes according to a common start time in order to ensure a properly timed laydown of warheads and bombs that minimized the chances of 'fratricide'. A 'Free Launch Schedule' (FLSS) governed the release timing of every weapon, or 'sortie', for the SIOP then in effect. Mistakes calculating the FLSS timing for delayed Minuteman sorties was one of the more common critical errors in crew training.

The SIOP in effect at the time envisioned a series of salvos beginning with a large-scale strike at opposing nuclear forces – the counterforce phase of conflict meant to achieve so-called “escalation dominance” and position the United States to coerce the Soviet Union into throwing in the towel. This phase would have begun with either a preemptive U.S. first strike or, if the Soviets managed to fire first, we trained extensively to launch promptly on warning of incoming Soviet warheads and thus avoid the destruction of Minuteman (and Titan) missiles on the ground or in the first few minutes of flight. After a pause of a few hours to assess the adversary's reactions and speculative intentions, the president or his successor would have either authorized the termination of the offensive strikes using a special EAM or escalated the conflict to, say, large-scale strikes against enemy war- supporting industry using a second Red Dot 1 message with a new war plan number.

The final Red Dot 1 message envisioned would have called for an all-out strike against the enemy's top civilian and military leadership once hope of a negotiated end to the war had been abandoned. (Due largely to critical deficiencies and vulnerabilities in nuclear command, control, communications and intelligence (C3I) – the post attack airborne command system with “Looking Glass” was the backbone of nuclear warfighting C3I -- our exercises and training always culminated in all-out war). Today's nuclear war plans allow for more flexibility in the size and sequence of strike operations; for instance, an initial strike may be directed against the opposing leadership and sequence in the opposite direction from the early 1970s plan.

Prior to execution, the nuclear forces and wartime C3 system were governed in the early 1970s by the procedures and conditions outlined by the various Defense Readiness Conditions (DEFCONs), and by 'Posture' EAMs. For example, an increase from the normal peacetime DEFCON 4/5 to DEFCON 2 would have entailed minimizing non-essential communications (MINIMIZE in the declassified “Checklist”) and the dispersion of secondary battle staffs. For example, I served at the 'Kilo' underground Minuteman launch center which had the additional responsibility of serving as the Wing Alternate Command Post. If we had gone to DEFCON 2 a wing battle staff of senior officers would have descended upon our cramped facility. (This may be the “provisional task force” for DEFCON 2 mentioned on page 4 of the “Checklist”). If they never made it, the duties of wing battle staff managing 200 Minuteman missiles would have fallen on the shoulders of my crewmate and me. We did not possess the authority to fire missiles without SAS authorization, but we possessed the technical ability to fire up to 50 missiles and/or to format and transmit a valid and authentic Red Dot 1 message that would have triggered SIOP execution by all the strategic forces except the bomber force (which required a special unlock code that we did not possess).

In the early 1970s, SAC’s “Posture” messages (called “Blue Dot” messages in the 1964 Checklist) were intended primarily to shorten the reaction time of strategic bomber and other strategic aircraft so that they could be flushed into the air on tactical warning of an incoming nuclear strike in time to ensure their successful take off and survival. These Posture messages would have been issued by the senior SAC commander (or lower-level commanders if SAC communications were disrupted) upon notification that North America appeared to be under nuclear missile attack. Bombers taking off under a 'positive control launch, or PCL' would have proceeded (with re-fueling along the way) to their 'fail-safe' positions a hundred or more miles from enemy territory. These were the positive control turnaround points (PCTP), which were located just outside the line-of-sight radar range of enemy territory in order not to trigger Soviet air defense operations and otherwise escalate tensions.

At some point during this journey to their PCTAPs, the bomber crews might have received a radio transmission, probably over High Frequency from higher command or perhaps by Ultra-High Frequency Red Dot 1 messages transmitted to them by aircraft relays (e.g. refueling tankers) or by Minuteman Emergency Rocket Communications System missiles fired out of Whiteman Air Force Base’s Minuteman special squadron. The Red Dot 1 message with less than 30 characters (spelled out it was still only half the length of a tweet today) would probably have been a voice message designating an Execution Reference Time and war plan number as well as unlock codes (to unlock their bomb racks in flight). This EAM to the bombers would have thus confirmed or possibly reprogrammed their final mission folder, targets, routes and bomb drop timing.

If a nuclear strike was aimed at China (or North Korea) alone, a Blue Dot EAM would have been used to prepare the bomber and submarine forces to execute it. To the best of my recollection (bomber EWO was not taught to Minuteman crews), a Red Dot 1 would not have been used because its war plan numbers would have involved strikes by U.S. Minuteman missiles whose great circle ballistic trajectories would have taken them over Soviet territory enroute to Asia. By the early 1970s if not earlier it was well recognized that such overflights by large numbers of U.S. missiles might cause Soviet misinterpretation and trigger a Soviet launch against the United States. Therefore, the main strategic nuclear war plans against China involved only strategic bombers and submarines whose routes and trajectories could circumvent Soviet territory, and I believe Blue Dot messages would have provided the EWO guidance. If the United States had gone to war with both the Soviet Union and China, then a Red Dot 1 message would have been sent to all three components of the U.S. strategic forces including Minuteman and Titan missile crews.

The Red Dot 1 nomenclature and mission that I was familiar with were compromised at least twice: once by an American spying for the Soviet Union, who evidently disclosed these secrets in the late 1960s, and a second time by a misguided young SAC officer in the early 1980s.

In the first instance, the compromise was not discovered and the Soviets thus acquired the ability to determine whether the United States was transmitting a SIOP EAM. Since during much of the 1960s, 1970s, and early 1980s such SIOP directives would likely have been disseminated over insecure voice communications (especially the Primary Alerting System), it is quite possible that Soviet communications monitoring would have intercepted the SIOP message at the same time that it was being passed to the U.S. executing forces. It is thus likely that the Soviets would have known a large-scale strategic strike was imminent and taken steps to preempt it or to be better prepared to launch on warning. It is also possible that the Soviets learned from this spy how to inject nuclear EAMs into the Naval Broadcast Communications Network, a compromise that was not discovered until the mid-1990s when it led the Navy to revise its SSBN launch authorization procedures in case they received a Red Dot 1 (or the newer flag word that replaced it) out of the blue.

In the second instance, the discovery of the compromise in the early 1980s led the Joint Chiefs of Staff, National Security Agency, and Strategic Air Command to devise new flag-words for execution EAMs, which may be still classified. If this second discovery had not happened, it is possible that the Soviets and later the Russians might have continued to have the ability to detect in real time the dissemination of U.S. Red Dot I directives to execute the SIOP. On a personal note, I asked the late Helmut Sonnenfeld, a former senior assistant to Henry Kissinger, who was married to an heiress of the Hecht family department store business in Washington, D.C., to inquire whether Hecht's would stop using Red Dot words and icons for their "special" sales in their local advertising during the 1980s. I and I imagine many others around town nearly had heart attacks when we turned the page in the Washington Post and came face to face with a flag word portending the onset of Armageddon.

 

Notes

[1] See, for example, Paul Bracken, The Command and Control of Nuclear Forces (New Haven, CT: Yale University Press, 1983), at 22: “…the exact details of how America’s nuclear forces would go to war are justifiably classified…”  Since Bracken wrote, much information about the SIOP and nuclear war planning has been declassified, including some details about the early “Football,” but procedural information has remained classified.

[2] The unusual assignment of an ICBM squadron to a reconnaissance wing was purely a temporary administrative matter. As the senior SAC organization at Forbes AFB, the 55th SRW acquired the 548th Strategic Missile Squadron (SMS) on 1 August 1964 when its parent SAC 40th Strategic Aerospace Wing and 21st Strategic Air Division inactivated. The 548th SMS was itself inactivated on 25th March 1965 after its last missile was removed on 8 February.

[3] The 55th SRW was SAC’s premier peripheral reconnaissance unit. On 1 July 1960, two months after the loss of a Central Intelligence Agency (CIA) U-2 over the USSR, a Soviet MiG-19 Farmer attacked and shot down a 55th SRW RB-47H operating from RAF Brize Norton in England. During 1966 the wing relocated to Offutt AFB, NE, where it remains operational. C. Mike Habermehl and Robert S. Hopkins, III, Boeing B-47 Stratojet: Strategic Air Command’s Transitional Bomber (Manchester, England: Crécy Publishing, Ltd., 2018), 127-31, 153-67; and Robert S. Hopkins, III, Spyflights and Overflights: U.S. Strategic Aerial Reconnaissance, vol. 1, 1946-1960 (Manchester, England: Crécy Publishing, Ltd., 2016), 38-59.

[4]. Robert S. Hopkins, III, Boeing KC-135 Stratotanker: More Than a Tanker (Manchester, England: Crécy Publishing, Ltd., 2017), 72-77. For the Thule accident, see “Newly Released Sandia Labs Film Presents Story of U.S. Nuclear Weapons Safety Effort,” National Security Archive Electronic Briefing Book 498, December 23, 2014.

[5]. This was a pre-delegated chain of command beginning with the Vice CINCSAC followed by SAC’s Numbered Air Force (NAF) commanders based on date of rank, with the Airborne Emergency Action Officer—AEAO—on a SAC airborne command post serving as interim commander until the successor was in place. The AEAO was designated as the final commander should the others be inaccessible. History of Strategic Air Command, July-December 1966, 7-11. 

[6]  Alert categories such as Alfa and Charlie should not be confused with mission tasking as defined by National Strategic Targeting and Attack Policy (NSTAP). For example, under SIOP-4, the NSTAP stipulated three major “tasks” which could be executed in any of five primary attack options. Alpha and Bravo were strictly counterforce missions aimed at time-urgent nuclear threat targets and non-nuclear military forces respectively, while the Charlie task targeted war-supporting urban-industrial targets.  See General Maxwell Taylor to General LeMay et al., “Review of the SIOP Guidance,” 5 June 1964, 10-13.

[7]. On the operational history of PACCS, see Hopkins, Boeing KC-135 Stratotanker, Chapter 9, “Managing Nuclear War”; and Habermehl and Hopkins, B-47 Stratojet, 70-72.

[8].Scott Sagan, The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton: Princeton University Press, 1993). 78.

[9]. L. Wainstein et al;,  The Evolution of U.S. Strategic Command and Control and Warning, 1945-1972 (Arlington, VA: Institute for Defense Analyses, 1975), 329, National Security Archive Electronic Briefing Book 403, Document 2, November 19, 2012