Reframing the Nuclear De-alerting Debate: Towards Maximizing Presidential Decision Time

Reframing the Nuclear De-alerting Debate: Towards Maximizing Presidential Decision Time

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Andrew Brown

Research Associate, The James Martin Center for Nonproliferation Studies

Jeffrey Lewis

Director of the East Asia Nonproliferation Program, The James Martin Center for Nonproliferation Studies

President Obama, March 15, 2009
Wikimedia Commons

More than twenty years after the end of the Cold War, it remains the case that Russian nuclear-armed intercontinental ballistic missiles (ICBMs) can reach the United States-and U.S. ICBMs Russia-in less than thirty minutes. U.S. launch processes for ICBMs and SLBMs (submarine-launched ballistic missiles) require only two and twelve minutes, respectively. These statistics impose extreme time constraints-a maximum of eighteen to twenty-eight minutes-on both U.S. command-and-control systems and the U.S. presidential decision-making process. Following a hypothetical Russian launch of nuclear ICBMS, crews in early warning centers would have to identify and correctly characterize an attack before reporting their findings up the chain of command. Senior nuclear commanders would then have to enumerate for the president his or her nuclear strike options and their consequences. These firm time constraints and rigid routines would leave the U.S. President with "at most twelve minutes to decide whether and how to respond with nuclear weapons." [1] This issue brief will explore the risks of accidental launch, unauthorized use or miscalculation posed by U.S. and Russian alert nuclear forces. The brief also considers various policy options, both implemented and proposed, to minimize these risks and maximize the time available to the U.S. president to decide whether or not to authorize nuclear war.

Assessing the Status Quo

During his successful 2007 campaign for the U.S. Presidency, then-Senator Barack Obama told a crowd at DePaul University that U.S. nuclear forces, policy and posture remained "focused on deterring the Soviet Union (USSR) – a country that doesn't exist." [2] Among other commitments, Obama promised that, if elected, he would "work with Russia to take U.S. and Russian ballistic missiles off hair-trigger alert." [3] In the 2010 Nuclear Posture Review (NPR), however, the Obama Administration ultimately concluded that the "current alert posture of U.S. strategic forces … should be maintained for the present." [4] Regarding the President's campaign promise to reduce the alert rates of ballistic missiles, the Nuclear Posture Review "considered the possibility of reducing alert rates for ICBMs and at-sea rates of SSBNs, and concluded that such steps could reduce crisis stability by giving an adversary the incentive to attack before 're-alerting' was complete." [5] The Nuclear Posture Review did, however, propose a series of measures to "diminish further the possibility of nuclear launches resulting from accidents, unauthorized actions, or misperceptions, and to maximize the time available to the President to consider whether to authorize the use of nuclear weapons." [6] These measures included endorsing the current practice of 'open-ocean targeting,' proposing further investments in the nuclear command-and-control system, and initiating a study to explore new modes of ICBM basing. [7]

This is not the first time that a President, once in office, has tempered campaign rhetoric concerning revisions to the U.S. nuclear posture. In 2000, then Governor George W. Bush criticized the Clinton administration for remaining "locked in Cold War mentality." Governor Bush further asserted that, "the United States should remove as many weapons as possible from high-alert, hair-trigger status…" [8] However, the Bush Administration's 2002 Nuclear Posture Review, concluded that U.S. nuclear forces could not be considered to be on "hair trigger alert," and that rigorous safeguards existed to ensure the highest levels of nuclear weapons safety, security, reliability, and command-and-control. [9]

'Hair trigger' is a phrase that conveys a subjective judgement about the risk of an accidental, unauthorized or mistaken use of U.S. nuclear weapons, relative to the benefit of maintaining ready forces. U.S. Strategic Command (STRATCOM) rejects the characterization of U.S. nuclear forces as being on 'hair trigger' alert because this characterization "ignores the safeguards, deliberate actions, and procedures required in order to employ nuclear weapons." [10] STRATCOM describes the most ready U.S. nuclear forces as being on "day-to-day" alert status. Despite having reduced dramatically both the number of nuclear weapons and delivery systems maintained on day-to-day alert, including all bombers, since 1991, the United States still maintains nearly all 450 of its ICBMs and several of its nuclear ballistic missile submarines at sea on day-to-day alert. As such, just under 1,000 U.S. nuclear warheads are on so-called day-to-day alert. [11]

The Cold War Context

The concept of day-to-day alert status dates back to Cold War concerns about a surprise attack. For both Washington and Moscow, the Second World War began with a surprise attack-the German offensive against the Soviet Union in June 1941, followed by Japan's surprise attack on Pearl Harbor in December 1941. Surprise remained a constant theme throughout the Cold War, as both sides remained wary of a "bolt from the blue." The United States countered the fear of a surprise attack by placing a significant portion of U.S. nuclear forces on alert. Starting in 1958 and lasting through the 1960s, U.S. Strategic Air Command kept a portion of the bomber force on constant airborne alert, under various names including Head Start, Chrome Dome, Hard Head, Round Robin and Giant Lance.

As the total number of U.S. and Soviet nuclear weapons and delivery vehicles increased, planners began to worry less about a comprehensive disarming attack than a targeted attack intended to kill their nation's leaders, as such a strike could leave a decapitated military unable to retaliate. In the catastrophic event of a series of nuclear explosions, all communications systems (cables, radio and satellite channels) would be susceptible to disruption from the resulting electromagnetic pulse, blast and radiation effects. Because the critical infrastructure of the nuclear command, control, and communications (NC3) network would be prioritized by an adversary in any hypothetical target selection, this network would be particularly vulnerable to destruction in a nuclear first strike. The United States responded to fears of decapitation with a number of measures, which included building underground facilities at Raven Rock and Mount Weather, developing the Airborne Command Post and, handing off the "nuclear football" containing U.S. nuclear launch codes to a military aide never far from the President.

The USSR, too, worried about a disarming U.S. nuclear attack and kept a significant portion of its nuclear arsenal in a comparable "state of combat readiness." The Soviets were much more concerned about a decapitating first strike than the Americans. They carved their underground command post, known as Grot, into a mass of granite in the Ural Mountains. Grot would have shielded commanders from nuclear war while allowing radio signals to penetrate, maintaining Soviet command-and-control capabilities. To ensure an ability to launch a retaliatory strike even after an initial volley of U.S. ICBMs hit their targets, the Soviets developed what David Hoffman describes as "one of the most creative, astonishing and frightening inventions of the Cold War." [12] Approved for development in 1974, Perimeter was a semi-automatic system for launching a retaliatory nuclear strike. Designers conceived of command missiles, kept in super-hardened silos and launched at the onset of a nuclear exchange. Instead of a warhead, these command missiles would carry advanced electronics. Soaring safely above the catastrophic conditions on the ground, the command missiles could broadcast the launch order to the surviving ICBMs. Communication would be preserved, and thus, retaliation assured. The Soviet Union deployed Perimeter in 1985. [13]

Risk Minimization: Technical and Procedural Solutions

The existence of large numbers of nuclear weapons on alert has created what Peter Stein and Peter Feaver describe as the "always/never dilemma." [14] The military must always be able to use nuclear weapons at a moment's notice and under every conceivable circumstance. While fulfilling this exacting requirement, the military must never have a serious accident, never permit the unauthorized use of nuclear weapons, and never use nuclear weapons as a result of a miscalculation. [15] Experts such as Scott Sagan have expressed concern that U.S. and Russian forces, alert to one another, may represent a so-called "tightly coupled system" that runs an unnecessary risk of accident, unauthorized launch or miscalculation. "Tightly coupled systems tend to have plans for very rapid reactions," Sagan wrote. "They have time-dependent and invariant production processes, little slack, and little opportunity for improvisation once problems occur." [16] In a nuclear force on alert, there exists highly "institutionalized predispositions to respond quickly and massively to an enemy nuclear provocation." [17]

In light of the always/never dilemma, the United States instituted elaborate technical and procedural solutions during the Cold War to minimize the risks of accidental, unauthorized, or mistaken use of nuclear weapons. Permissive Action Links (PALs) were introduced to preclude unauthorized arming or detonation of nuclear weapons. After a number of accidents, Strategic Air Command (SAC) removed the nuclear-armed B-52 bombers from constant airborne alert. [18] In December 1990, then Secretary of Defense Dick Cheney chartered an independent Federal Advisory Committee on Nuclear Failsafe and Risk Reduction (FARR) to assess the current and programmed command and control system's "capability to meet the dual requirements of unauthorized use of nuclear weapons and assurance of timely, reliable execution when authorized, and to identify opportunities for positive measures to enhance failsafe features." [19] On 27 September 1991, as part of the Presidential Nuclear Initiatives (PNIs), George H.W. Bush removed all bombers from day-to-day alert. [20]

While confident in the technical and procedural safeguards in place to prevent accidental, unauthorized or mistaken use of U.S. nuclear weapons, the Clinton Administration was deeply concerned about the alert status of Russian forces. In January 1995, Russia reportedly mistook the launch of a U.S.-Norwegian sounding rocket for a missile launch. [21] The Clinton Administration undertook a number of efforts to address concerns about the quality of the Russian warning system directly. [22] Presidents Clinton and Yeltsin agreed to a series of measures, including a de-targeting agreement and provisions to exchange information on missile launches and early warning. The exchanges included the cooperative development of a Russian American Observations Satellite or (RAMOS) and the "possible establishment of a center for the exchange of missile launch data operated by the United States and Russia and separate from their respective national centers." [23] The envisioned Joint Data Exchange Center (JDEC) never materialized and, despite serious efforts, the initiative languished throughout the Clinton and Bush administrations. The Obama administration attempted to revive the JDEC initiative in the form of a Data Fusion Center, although with little success.

Lengthening the Fuse: The De-alerting Debate

Despite the implementation of some risk reduction measures, many observers continue to worry that the alert status of U.S. and Russian nuclear forces present an unacceptable risk of accidental, unauthorized or mistaken use of nuclear weapons, particularly in a post-Cold War world. Some of these observers have proposed so called "de-alerting" measures. Early proposals focused on "lengthening the fuse on nuclear weapons by increasing the preparation time needed to launch." [24] These discussions focused on implementing reversible physical modifications to U.S. and Russian delivery systems that would make it impossible to launch without a relatively time-consuming effort. The spectrum of possible physical de-alerting measures suggested included safing Minuteman missiles in their silos by pinning open their safety switches to electronically isolate them from outside launch signals; covering missile silos with several meters of soil; refraining from installing electronic devices known as inverters on the missile tubes of SSBNs; removing guidance or control modules from missiles; removing tritium bottles from boosted and thermonuclear warheads; and removing warheads completely and placing them in secure storage separate from their associated delivery systems.

De-alerting measures have found little support within the U.S. government. The Defense Science Board Task Force on Nuclear Deterrence, for example, warned that "to do violence to the stability of the force over a perceived danger not addressed by de-alerting U.S. systems seems unwise in the extreme." [25] In particular, the Defense Science Board and others warned that reversible physical modifications to reduce the readiness of U.S. strategic forces – what might be called physical time extenders – may worsen risks associated with alert forces because of the uncertainty created during a hypothetical deterioration of the international security environment requiring "re-alerting." In a crisis, each side might feel the need to begin re-alerting nuclear forces on a rigid time schedule, running the risk that the other side might attempt an early attack. Lengthening the time necessary to use some nuclear forces, without making corresponding adjustments in strategy and doctrine, may actually have the perverse effect of worsening the pressure on presidential decision-making in the midst of a crisis.

Putting Time on the Clock

It may be more constructive to think in terms of putting time on the clock rather than lengthening the fuse, as suggested by the 2010 U.S. Nuclear Posture Review. To further strengthen strategic stability at lower force levels, the 2010 NPR suggested a number of measures to maximize Presidential decision time. First, the United States will continue the practice of open-ocean targeting of all ICBMs and SLBMs so that, in the remote event of an unauthorized or accidental launch, the missile would land in the open ocean. As part of this first measure, "the U.S. will ask Russia to re-confirm its commitment to this practice." [26] Second, the United States will make unspecified new investments in the command and control system to maximize Presidential decision time in a nuclear crisis. [27] Third, the U.S. Department of Defense will "explore new modes of ICBM basing that could enhance survivability and further reduce any incentives for prompt launch." [28] The report on the recently revised Nuclear Employment Strategy, submitted to Congress by the Secretary of Defense on behalf of the President, directs the Department of Defense "to examine further options to reduce the role Launch Under Attack (LUA) plays in U.S. planning, while retaining the ability to Launch Under Attack if directed." [29]

These measures may make a small difference at the margins. Reaffirming open-ocean targeting was a worthwhile step in the 1990s, but it guards only against the vanishingly unlikely possibility of an accidental launch. A new generation of mobile missiles might increase survivability, but the experience of the MX and Small ICBM during the 1980s suggests that the Air Force will not be able to afford a new fleet of mobile ICBMs in the current environment of fiscal austerity.

If the U.S. President wants more decision-time, he must make ask for it. Specifically, the President will need to issue nuclear weapons employment guidance that makes clear the premises for sizing and posturing nuclear forces are now different. Deterrence now rests more on the President having the ability to respond in the time and manner of his choosing, rather than on a small number of rigid preplanned operations to be executed under crushing time pressures. The President should replace the requirement for a prompt response with one requiring multiple options premised on U.S. nuclear forces being withheld for days or longer before any retaliation. The President would direct the military to deploy and exercise forces on the assumption that retaliation would occur over the course of days. The President would also require the ability to task the military to generate new tailored options in response to the specific situation. Some nuclear forces would, of course, remain on day-to-day alert; nothing in the new guidance would prohibit the existence of alert forces. But it is important for the President to make clear that the purpose of placing nuclear forces, such as ballistic missile submarines, on alert is to provide the decision-making time necessary to confirm the fact, size, and origins of any attack before authorizing the launch of U.S. nuclear weapons.

[1] Global Zero U.S. Nuclear Policy Commission Report, “Modernizing U.S. Nuclear Strategy, Force Structure and Posture” (May 2012)
[2] Barack Obama, “A New Beginning.” DePaul University, Chicago, Illinois, 2 October 2007,
[3] Barack Obama, “A New Beginning.” DePaul University, Chicago, Illinois, 2 October 2007,
[4] Department of Defense, Nuclear Posture Review Report, (April 2010)
[5] Department of Defense, Nuclear Posture Review Report, (April 2010)
[6] Department of Defense, Nuclear Posture Review Report, (April 2010)
[7] Department of Defense, Nuclear Posture Review Report, (April 2010)
[8] George W. Bush. “New Leadership on National Security.” Washington, D.C. 23 May 2000,
[9] Although the 2002 Nuclear Posture Review remains classified, an unclassified summary was prepared for the 2002 Secretary of Defense Annual Defense Review. Portions of the 2002 Nuclear Posture Review were also leaked to the press. The leaked portion contains the statement that U.S. nuclear forces are not on hair trigger alert.
[10] “Text of Nov. 28 E-mail from Strategic Command responding to ACT’s questions on the alert status of U.S. nuclear weapons” (November 2007)
[11] “Text of Nov. 28 E-mail from Strategic Command responding to ACT’s questions on the alert status of U.S. nuclear weapons” (November 2007)
[12] D. Hoffman, The Dead Hand (Anchor Books) 2009 p. 150.
[13] D. Hoffman, The Dead Hand (Anchor Books) 2009 p. 150.
[14] Peter Feaver, Guarding the Guardians: Civilian Control of Nuclear Weapons in the United States (Cornell University Press) 1992 p. 12.
[15] Bruce Blair, Strategic Command and Control: Redefining the Nuclear Threat (The Brookings Institution) 1985 p 288.
[16] Scott Sagan, The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton University Press) 1993 p. 277.
[17] Bruce Blair, Strategic Command and Control: Redefining the Nuclear Threat (The Brookings Institution) 1985 p 288.
[18] (October 1959) A B-52 collided with a KC-135 during a refueling operation south of Louisville, Kentucky and crashed with two nuclear weapons onboard; (January 1961) An airborne alert B-52 broke apart in midair. Two thermonuclear weapons landed on a farm near Goldsboro, North Carolina; (March 1961) A B-52 carried two nuclear weapons crashed near Yuba City, California after it failed to rendezvous with a refueling tanker and ran out of fuel; (January 1966) B-52 on a training mission collided with a KC-135 during a refueling operation near the coast of Spain. Both aircraft crashed near Palomares.
[19] Department of Defense, Final Report of the Federal Advisory Committee on Nuclear Failsafe and Risk Reduction (1992)
[20] George H.W. Bush. “Address to the Nation on Reducing United States and Soviet Nuclear Weapons” Washington, D.C. 27 September 1991,
[21] (January 1995) U.S. and Norwegian scientists launched a four-stage sounding rocket off the northwestern coast of Norway, carrying scientific equipment to study the aurora borealis. The rocket lit up the Russian early-warning system and the nuclear weapons command suitcase was brought to Boris Yeltsin.
[22] Department of Defense, Report of the Defense Science Board Task Force on Nuclear Deterrence (October 1998) p. 15,
[23] William Clinton and Boris Yeltsin. “Joint Statement on the Exchange of Information on Missile Launches and Early Warning” Moscow, Russia (2 September 1998)
[24] B. Blair, “De-Alerting Strategic Nuclear Forces” from H. Feiveson (ed) The Nuclear Turning Point: A Blueprint for Deep Cuts and De-Alerting of Nuclear Weapons (The Brookings Institution) 1999 p. 101.
[25] Department of Defense, Report of the Defense Science Board Task Force on Nuclear Deterrence (October 1998) p. 15,
[26] Department of Defense, Nuclear Posture Review Report, (April 2010)
[27] Department of Defense, Nuclear Posture Review Report, (April 2010)
[28] Department of Defense, Nuclear Posture Review Report, (April 2010)
[29] Department of Defense, Report on the Nuclear Employment Strategy of the United States Specified in Section 491 of 10 U.S.C. (19 June 2013).

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Leaders must untie the ‘knot of war’ in Europe


Leaders must untie the ‘knot of war’ in Europe

“The risk of an accident, miscalculation, or disastrous decision is especially ominous when the two countries with the largest nuclear weapon arsenals are on opposite sides.”


Intercontinental ballistic missile (ICBM)
Intercontinental ballistic missile (ICBM): A ballistic missile with a range greater than 5,500 km. See entry for ballistic missile.
Submarine-launched ballistic missile (SLBM)
SLBM: A ballistic missile that is carried on and launched from a submarine.
Ballistic missile
A delivery vehicle powered by a liquid or solid fueled rocket that primarily travels in a ballistic (free-fall) trajectory.  The flight of a ballistic missile includes three phases: 1) boost phase, where the rocket generates thrust to launch the missile into flight; 2) midcourse phase, where the missile coasts in an arc under the influence of gravity; and 3) terminal phase, in which the missile descends towards its target.  Ballistic missiles can be characterized by three key parameters - range, payload, and Circular Error Probable (CEP), or targeting precision.  Ballistic missiles are primarily intended for use against ground targets.
Nuclear Posture Review
Under a mandate from the U.S. Congress, the Department of Defense regularly conducts a comprehensive Nuclear Posture Review to set forth the direction of U.S. nuclear weapons policies. To date, the United States has completed four Nuclear Posture Reviews (in 1994, 2001, 2010, and 2018).
Ship, Submersible, Ballistic, Nuclear: A hull classification for a submarine capable of launching a ballistic missile. The "N", or nuclear, refers to the ship's propulsion system. SSBN's are generally reserved for strategic vessels, as most submarine launched ballistic missiles carry nuclear payloads. A non-strategic vessel carries the designation SSN, or attack submarine.
Electromagnetic Pulse (EMP)
A sharp pulse of radio-frequency (long wavelength) radiation produced when an explosion occurs in an asymmetrical environment, especially at or near the earth's surface or at high altitudes. The intense electric and magnetic fields can damage unprotected electrical and electronic equipment over a large area.
Radiation (Ionizing)
Radiation that has sufficient energy to remove electrons from substances that it passes through, forming ions. May include alpha particles, beta particles, gamma rays, x-rays, neutrons, high-speed electrons, high-speed protons, and other particles capable of producing ions.
First strike
First strike: The launch of a surprise attack intended to considerably weaken or destroy an adversary's military infrastructure or nuclear forces, and thus severely reduce the adversary’s ability to attack or retaliate.
Hardened underground facility for housing and launching a ballistic missile.
An aircraft carrying conventional or nuclear bombs, or conventionally or nuclear-armed cruise missiles, for use against ground or sea targets.
Presidential Nuclear Initiatives (PNI)
PNI: A series of initiatives announced in 1991 by U.S. President George H. W. Bush and Soviet General Secretary Mikhail Gorbachev, declaring that their two countries would reduce tactical nuclear weapons arsenals and associated delivery systems.
Thermonuclear weapon
Thermonuclear weapon: A nuclear weapon in which the fusion of light nuclei, such as deuterium and tritium, leads to a significantly higher explosive yield than in a regular fission weapon. Thermonuclear weapons are sometimes referred to as staged weapons, because the initial fission reaction (the first stage) creates the condition under which the thermonuclear reaction can occur (the second stage). Also archaically referred to as a hydrogen bomb.


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