35+ Years of Freedom of Information Action

The “Launch on Warning” Nuclear Strategy and Its Insider Critics

Launch control officer, seated at launch control panel, turns switch to start launching sequence. Testing operational readiness of Minuteman crews using Modified Operational Missiles
Published: Jun 11, 2019
Briefing Book #674

Edited by William Burr

Update for Briefing Book #43 originally posted in April 2001

For more information, contact:
202-994-7000 or nsarchiv@gwu.edu

Policy Adopted in 1970s, Still in Effect Today Despite Danger of False Alerts

Top Defense Official in 1978 Called It “Dangerous, Wrong, and Ineffective”

Reagan Directive Called for Leaving Soviet Planners “with Strong Uncertainty” about U.S. Response to Warning

Washington, D.C., June 11, 2019 – “Launch-on-warning,” a feature of U.S. nuclear warfighting strategy since the late 1970s, has frequently faced intensive criticism because of the high risk of accidental launches and uncontrollable outcomes, including massive casualties, according to recently declassified records posted today by the nongovernmental National Security Archive.

Yet, successive presidential administrations have stood by a prompt-launch approach. The new documents, obtained through archival research and declassification requests, are combined here with an earlier National Security Archive e-book to further illuminate high-level thinking about a key aspect of nuclear war planning the public rarely hears about.

Two newly declassified highlights in the posting are White House adviser William Odom’s critique of launch-under-attack and President Ronald Reagan’s National Security Decision Directive 13, which provided criteria for nuclear war planning, including launch-on-warning as a way to keep Moscow "uncertain."



In the fall of 1979, as the Carter administration was revamping U.S. nuclear strategy, Lt. Colonel William Odom, an official on the White House national security staff, raised doubts about the recent inclusion of a launch-under-attack option in the nuclear war plan, the Single Integrated Operational Plan (SIOP).  In a memorandum published today by the National Security Archive, Odom argued against rapid launching of Minuteman missiles in response to electronic warnings because warning systems were “just not good enough to let us know that our ICBMs are under attack.”  Moreover, according to Odom, not enough thought had been given to the launch-under-attack targets: they would strike “empty Soviet silos.”  Further, if the U.S. launched a follow-up nuclear attack, the nuclear explosions and radiation effects caused by a launch-under-attack strike could destroy incoming U.S. missiles through “fratricide.” Launch-under-attack as a SIOP option, Odom advised, should be cancelled.

Odom’s advice was disregarded but since then, presidents, presidential candidates, former officials, and defense policy experts have questioned the U.S.’s reliance on a high-alert, instant reaction posture for Minuteman missiles that provide a launch-on-warning capability.  When he was a presidential candidate George W. Bush declared that “keeping so many weapons on high alert may create unacceptable risks of accidental or unauthorized launch.”  His successor, Barack Obama, highly aware of the danger of nuclear weapons, explicitly called for reducing the role of launch-under-attack in U.S. nuclear planning. Yet, neither president changed the quick-reaction/launch-on-warning posture, perhaps to avoid a conflict with the Pentagon.

Today’s publication updates a National Security Web posting from April 2001, “Launch on Warning: The Development of U.S. Capabilities, 1959-1979.”  The original documents are included in addition to more recently declassified items, , not only the Odom memorandum cited above, but records on policy development during the Carter and Reagan administrations when launch-on-warning and launch-under-attack postures were incorporated into the SIOP and official “nuclear weapons employment policy.”

Among the new documents are:

  • Excerpts from a 1968 Strategic Air Command history suggesting that a “a fire on warning doctrine was the best military answer” to the possible threat of strikes by Soviet submarine-launched missiles on U.S. ICBM sites to prevent successful launches of the missiles.
  • A Project RAND report from 1975 that stated that once the President had made a launch decision, Minuteman ICBMs would reach high altitudes in “about seven minutes.”
  • A Carter administration critique of launch-under-attack included the observation that “the President could decide to retaliate in a few minutes [but] he shouldn't, as a matter of policy, have to do so.”
  • The Carter administration Defense Department’s support for launch-under-attack as a measure “designed to strengthen deterrence.”
  • The Reagan administration’s National Security Decision Directive 13 that stipulated that it was U.S. policy not “to rely on” launch-on-warning in an “irrevocable manner.”  With launch-on-warning not strictly prohibited, the U.S. “must leave Soviet planners with strong uncertainty as to how we might actually respond.”

During the Carter administration and the years that followed, defense officials along with journalists, political scientists, and policy analysts debated the risks of launch-under-attack/on warning.  Science adviser Richard Garwin saw it as a method to strengthen deterrence, while future Reagan administration official Fred C. Iklé decried it in the Washington Post. During the early 1980s, deeply critical assessments emerged sporadically as a result of hints that launch-on-warning or launch-on-attack had become embedded in Pentagon policy. The pros and cons attracted less attention, however, as a new détente emerged during Reagan’s second term.[1]

The end of the Cold War brought many changes, but not in the hair trigger alert status of the Minuteman ICBM force.  Bruce G. Blair, a former Minuteman launch officer who was at the Office of Technology Assessment and the Brookings Institution during the 1980s and 1990s, emerged as the most persistent and well-informed critic/analyst of launch-on-warning. Drawing on his personal experience and wealth of knowledge, Blair has written major studies of command-and-control vulnerabilities and accidental nuclear war, especially the danger of the U.S.’s hair-trigger alert posture for Minutemen ICBMs and the risk of an accidental launch because of a warning system failure. One of his studies for the Office of Technology Assessment, addressing command and control problems and launch-on-warning, was so highly classified by the Pentagon that it has proven impossible to locate, at least so far.[2]

The risks that Blair and others associated with launch-on-warning were the logical consequence of U.S. nuclear war plans. As soon as the Soviet Union and then China began to develop a nuclear weapons complex, U.S. military planners defined the most crucial installations slated for rapid destruction as "time urgent" high-value targets; they included air defense, nuclear command centers, and missile and air bases.  A capability to strike those targets as rapidly as possible, once warning information became available, became an enduring high priority for war planners.

The potential threat posed by Soviet nuclear forces prompted U.S. military commanders and intelligence agencies to look for signs that the Soviet leadership might be readying them for use in a surprise attack.  If Washington received "strategic warning" of an impending Soviet attack, top commanders wanted the option of a preemptive strike (sometimes called taking the “initiative”) against Soviet strategic and command and control targets. Consistent with this, the first SIOP, approved by President Dwight Eisenhower in the fall of 1960, included choices for preemptive and retaliatory nuclear strikes.[3]

When the U.S. Air Force began to deploy intercontinental ballistic missiles during the late 1950s, they envisaged a strategic force that could be launched within minutes to deliver enormously destructive nuclear weapons. The "Minuteman" ICBM embodied that idea.  While the possibility of rapid launch ICBMs supported ideas of preemptive attacks, preemption assumed strategic warning, specifically, intelligence indicating an imminent attack by an adversary, such as dispersal of nuclear forces and other signs of alerting and readiness activities. Whether such warning signs would be detected or properly interpreted is another matter.

If information became available that an attack was on the way – tactical warning intelligence – White House science advisers and Pentagon planners were reluctant to accept a strategy based on launching a retaliatory blow after absorbing a Soviet first strike.  According to White House science adviser and MIT professor Jerome Wiesner, once electronic sensors could detect the launch phase of a Soviet ICBM attack, they  could provide the "[warning] time necessary to ready our missiles so that they can be fired before they are destroyed."[4]  What Wiesner was pointing to was the possibility of a launch-on-warning capability, a prospect that other U.S. government officials were beginning to recognize during the early 1960s.

Not all defense planners accepted the logic of launch-on-warning and some were skeptical of preemption. Apparently, Secretary of Defense Robert McNamara had strong objections to launch-on-warning, which he held long after he had left the Pentagon.[5] For some top officials, the development of Soviet ICBMs raised doubts about preemption. During a grim briefing by the National Security Council's Net Evaluation Subcommittee (NESC) President Kennedy made one of his last documented statements about nuclear strategy.  Analyzing the consequences of U.S. and Soviet preemptive nuclear attacks on their respective societies, the NESC study introduced U.S. casualty figures---30 million--that were higher than Kennedy had heard before. With the devastating U.S. losses from Moscow's response to a preemptive strike, Kennedy observed that preemption was "not possible for us."[6]  Despite Kennedy's misgivings, a preemptive strategic option remains embedded in the SIOP and nuclear war plans to this day.[7]

The deployment of the Ballistic Missile Early Warning System (BMEWS) in the early 1960s provided a rudimentary capability for launch-on-warning by giving command authorities fifteen minutes’ tactical warning of a missile attack. Also, in the works during the 1960s and deployed in the early 1970s was a satellite-based electronic warning system originally known as the Missile Defense Alert System (MIDAS) but later camouflaged behind the designation, Defense Support Program (DSP).[8]

With the deployment of DSP satellites, the possibility of launch-on-warning became increasingly imbedded in policy discussion, arms control negotiations, and in the training of Minuteman launch officers.  Bruce Blair recalls that he “practiced LOW a hundred times during my Minuteman days 1972-74, which coincided with the U.S. DSP program becoming operational.”  Although some officials looked favorably at the prospects of launch-on-warning, others saw great risk.  One veteran official, Paul Nitze, warned that launch-on-warning would be "inexcusably dangerous" during a "time of intense crisis." What worried Nitze and others in particular was the danger of a false alarm, which was not a hypothetical problem. During the Cold War and after, both the United States and Russia received mistaken warnings of strategic attack, including the famous NORAD false warning incident on 9 November 1979.

When it was first published in 2001, this collection demonstrated the limits of the declassified record.  Few documents from military organizations, such as the Defense Department and the Strategic Air Command, had been declassified, although both played critically important roles in making launch-on-warning a capability.  Since then, however, significant defense-related records have become available that illuminate the development of the launch-on-warning posture and the technological developments that underlay it.  Exactly when strategic planners believed that a capability was actually at hand remains classified and it is likely, as Bruce Blair has suggested, that it was an evolutionary process.[9]

 In 1970, Caltech President and former Secretary of the Air Force Harold Brown, and a member of the SALT I delegation, found launch-on-warning tactically useful: it could make a Soviet attack on U.S. Minuteman fields "a relatively risky and unattractive" proposition.  Seeing launch-on-warning as a potential deterrent, when Brown became secretary of defense under President Jimmy Carter, he supported including a variant – launch-under-attack – in the SIOP. Initially, the option that Brown and others supported was an ICBM-only attack, but SAC later convinced him  that achieving SIOP objectives required a larger-scale attack involving bombers and SLBMs – the entire triad.[10] Documents from the late 1970s and early 1980s that have recently become available  shed light on the internal discussion of launch-on-warning and launch-under-attack and their significant role in the development of nuclear strategy.

Launch-under-attack is often used interchangeably with launch-on-warning. During the Cold War, the Joint Chiefs of Staff defined them identically: as a launch of forces between the detection of an attack and the arrival of the first warhead. According to Bruce Blair, pre-delegation instructions gave specific meaning to launch-under-attack because top military commanders with nuclear missions  would have to delay action until confirmation of an attack was available, although they would not have waited for evidence of massive destruction.  Under such circumstances, SAC defined the delayed reaction as a launch-under-attack.[11]  In any event, the point of both launch-on-warning and launch-under-attack was to ensure that ICBMs would be launched rapidly enough to destroy time urgent targets specified in war plans.

Soviet nuclear strategy is largely undocumented and no definitive information is available on the role of launch-on-warning in Soviet policy. Available information, however, suggests that by the late 1960s and early 1970s, defense planners considered preemptive, retaliatory, and launch-on-warning options.  Preemption had low feasibility because defense officials believed that U.S. nuclear forces were too widely dispersed to be destroyed by a first blow. Soviet defense officials saw launch after ride-out (“otvetnyy udar”) as an option by giving policymakers time for deciding on how to retaliate. Initially, top officials did not see launch-on-warning as a possibility because early warning systems were not effective enough to warrant a quick launch.  By the early 1980s, however, launch-under-attack had greater plausibility because Moscow had acquired some capability, mainly by hardening some ICBMs, such as the SS-18. against the effects of nuclear detonations.  With improvements in warning systems, Blair has argued, launch-on-warning became central to the Soviet and post-Soviet strategic posture. Indeed, Russian President Vladimir Putin’s October 2018 statements at the Valdai Discussion Club strongly suggest that Russia has a “counter-strike on warning” posture.[12]




[1]. Richard Garwin, “Launch Under Attack to Redress Minuteman Vulnerability?,” International Security 4 (1979/80): 117-139; Fred C. Iklé, "The Growing Risk of War by Accident,” Washington Post, 24 June 1980; Charles Mohr, “A Scary Debate Over ‘Launch Under Attack,’” New York Times, 18 July 1982; Hendrick Smith, “Colonel Stirs Question On MX-Firing Doctrine,” The New York Times, 8 April 1983;  William Broad, “Pershings Stir Accidental War Fears,” New York Times, 12 December 1983;  John Steinbrunner, “Launch Under Attack,” The Scientific American, 250 (1984): 33-41.

[2]. For Bruce Blair's writings see, in particular, The Logic of Accidental Nuclear War (Washington, D.C., Brookings Institution, 1993), and Global Zero Alert for Nuclear Forces (Washington, D.C., Brookings Institution, 1995).  For the Office of Technology Assessment study, see Tim Carrington, “The Ultimate Secret: A Pentagon Report Its Author Can't See – 'Nuclear Decapitation' Study Warns of Communication Being Destroyed in Crisis,” Wall Street Journal, 18 February 1986.  See also Bruce Blair, The End of Nuclear Warfighting: Moving to a Deterrence-Only Posture: An Alternative U.S. Nuclear Posture Review, with Jessica Sleight and Emma Claire Foley (Princeton, N.J. and Washington, D.C.:  Program on Science and Global Security, Princeton University, and Global Zero, 2019).

[3].  For accounts of early U.S. nuclear planning and the first SIOP, see Henry S. Rowen, "Formulating Strategic Doctrine," U.S. Commission on the Organization of the Government for the Conduct of Foreign Policy, Appendices, Vol. 4 (Washington, D.C., Government Printing Office, 1975), 217-34; David A. Rosenberg, "The Origins of Overkill: Nuclear Weapons and American Strategy, 1945-1960," Steven E. Miller, editor, Strategy and Nuclear Deterrence: An International Security Reader (Princeton, Princeton University Press, 1984), 113-82; and Scott D. Sagan, "SIOP-62: the Nuclear War Plan Briefing to President Kennedy," International Security 12 (Summer 1987): 22-51.

[4]. Blair, The Logic of Accidental Nuclear War, 170; Jerome Wiesner, "Warning and Defense in the Missile Age," 3 June 1959 (see document 2, below).

[5]. Robert S. McNamara, “No Second Use -Until,” The New York Times, 2 February 1983.  For McNamara, Blair, and others in the mid-1980s debate, see "Science and the Citizen," The Scientific American 255 (1986): 74-76.

[6]. U.S. State Department, FRUS 1961-1963, 8:499-502.

[7]. Blair, Logic of Accidental Nuclear War, 170.

[8]. For a valuable and comprehensive account of the history of MIDAS and DSP, see Jeffrey Richelson, America's Space Sentinels: DSP Satellites and National Security (Lawrence, KS, University of Kansas Press, 1999).

[9]. Blair, Logic of Accidental Nuclear War, 168.

[10]. Ibid, 186-187.

[11]. Ibid, 187; information from Bruce Blair, 14 May 2019.

[12]. Pavel Podvig, “Does Russia Have a Launch-on-Warning Posture? The Soviet Union Didn’t,” Russian Strategic Nuclear Forces, 29 April 2019;

Blair, Logic of Accidental Nuclear War, 195-216; William Burr and Svetlana Savranskaya, eds., “Previously Classified Interviews with Former Soviet Officials Reveal U.S. Strategic Intelligence Failure Over Decades,” National Security Archive Electronic Briefing Book 285, 11 September 2009; “Putin Meets with Members of the Valdai Discussion Club, Full Transcript of the Plenary Session of the 15th Annual Meeting,” 18 October 2018.

See also Simon Saradzhyan, “Putin’s Remarks on Use of Nuclear Weapons Are Confusing, But Unlikely to Constitute a Shift in Nuclear Posture,” Belfer Center for Science and International Affairs, Russia Matters, 28 November 2018.

[13]. For background, see the major study by Stephen Twigge and Len Scott, Planning Armageddon: Britain, the United States, and the Command of Western Nuclear Forces, 1954-64 (Amsterdam, Harwood Academic Publishers, 2000), 36-37, 117-119.

[14]. For more details on PSAC thinking about MIDAS, see Richelson, America's Space Sentinels, 12-13, 17

[15]. Jacob Neufeld, Ballistic Missiles in the United States Air Force, 1945-1960 (Washington, D.C., Office of Air Force History, 1990), 213-14

[16]. Richelson, America's Space Sentinels, p. 256, n. 37, citing an interview with Jack Ruina. If Schriever ever made an explicit case for launch-on-warning in writing it remains classified or unknown to this researcher

[17]. For McNamara's decision and later developments, see Richelson, America's Space Sentinels, 28-48.

[18]. According to Scott Sagan, "SAC and Air Force contractor personnel appear to have improvised their own safety procedures in a manner that seriously compromised Minuteman nuclear safety." See Sagan, The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton, Princeton University Press, 1992), 81-91.

[19]. For McNamara's decisions on the Minuteman force, see Stephen I. Schwartz et al., Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons Since 1940 (Washington, D.C., Brookings Institution, 1998),185-86, and Desmond Ball, Politics and Force Levels: The Strategic Missile Program of the Kennedy Administration (Berkeley: University of California Press, 1980).

[20]. Known also as Forward Scatter Radar, Over-the-Horizon (OTH) radar used high-frequency radio transmitters and receivers that were placed on either side of the Soviet Union and China. It would bounce continuous signals between the ionosphere and the earth until the signal reached the correct receiver. The system would detect a missile launch when it disrupted the stream of signals.

[21]. Bruce Blair communication with editor, 22 February 2001.

[22]. For the deployment of the DSP satellites during the late 1960s and early 1970s, see Richelson, America's Space Sentinels, 44-69.

[23]. Bruce Blair communication with the editor, 18 June 2019.

[24] Blair, Logic of Accidental Nuclear War, 342, note 40.

[25]. This resonates with a politico-military stratagem – the "Madman theory" – that has been associated with the Nixon administration: the notion that disproportionate threats and unpredictable irrationality could successfully coerce adversaries into compliance with U.S. goals. See William Burr and Jeffrey Kimball, Nixon's Nuclear Specter: The Secret Alert of 1969, Madman Diplomacy, and the Vietnam War (Lawrence: University of Kansas Press, 1998), 76-86.

[26]. E-mail from Pavel Podvig (editor of blog, Russian Strategic Nuclear Forces), 22 May 2019, drawing on his notes from the Vitalii Kataev papers (Hoover Institution Library and Archives, Stanford CA) and personal recollections.

[27]. For “jamming” the President in a crisis, see Bruce Blair, “Strengthening Checks on Presidential Nuclear Launch Authority,” Arms Control Today, January-February 2018, at 8.

[28]. For decisions on LUA, see Blair, Logic of Accidental Nuclear Warfare, 186.

[29]. Ibid., 168. For the downgrading of information confirming nuclear detonations in U.S. strategic planning during the 1980s, see ibid, 192.

[30]. For launch-on-warning policy as it developed during the Reagan administration, see Lee Butler, Uncommon Cause: A Life at Odds with Convention, Volume II: The Transformative Years (Denver, Outskirts Press, 2016), 10-12. For launch-on-warning not ruled out, see Michael Getler, “Joint Chiefs Back Plan for 100 MX,” Washington Post, 22 April 1982.