This policy brief is based on "No First Use: The Next Step for U.S. Nuclear Policy," which appears in the Fall 2010 issue of International Security.
The latest from BelferDespite heightened expectations for significant change in U.S. nuclear policy—especially declaratory policy—the Obama administration's Nuclear Posture Review changes little from the past. The NPR's declaratory policy retains the option for the United States to use nuclear weapons first in a variety of circumstances, including in a first strike against Chinese, North Korean, Russian, and (perhaps) future Iranian nuclear forces. Equally important, the United States can threaten the first use of nuclear weapons to deter and, if necessary, respond, to a variety of nonnuclear contingencies, including large-scale conventional aggression by another nuclear power such as China or Russia and chemical or biological weapons (CBW) attacks from states such as Iran and North Korea.
There are four reasons why the United States might decide to threaten, or actually use, nuclear weapons first: to deter or respond to conventional aggression; to deter or respond to chemical or biological weapons attacks; to preempt an adversary's use of nuclear weapons; and to hold at risk, and potentially destroy, underground targets. Upon close examination, U.S. conventional capabilities are more than sufficient for these missions, are more credible than nuclear threats, and do not carry the added political and military consequences associated with the United States breaking the long record of nuclear nonuse.
For the United States, deterrence of conventional aggression—the original justification for the threat of nuclear first use—is a Cold War relic. Given U.S. conventional advantages, the threat of first use is unnecessary for deterrence and unlikely to be perceived as credible by current and potential adversaries.
In recent years, the strongest argument for the United States to retain the first-use option has been that nuclear weapons are necessary to help deter, and possibly respond to, CW and especially BW attacks.
The necessity of retaining this option is grounded in part on the supposed success of nuclear deterrence in the 1990–91 Gulf War, where the United States implied that it might consider a nuclear response if Saddam Hussein used CW or BW. Yet the United States actually made two threats against the Hussein regime: an ambiguous threat of nuclear retaliation and an explicit threat of regime change. Although the documentary record is still incomplete, the available evidence suggests that the unequivocal threat of regime change, rather than the veiled threat of a nuclear response, was more influential in deterring Saddam.
In future crises involving CW- or BW-armed adversaries, the United States should employ a combination of conventional denial and punishment strategies. It should forcefully communicate that its deployed forces are equipped with appropriate defenses that will deny any potential benefits of the battlefield use of CW and BW. In addition, the United States should threaten an overwhelming conventional response, possibly coupled with the threat to capture and hold key decisionmakers responsible for their actions.
The third rationale for retaining the nuclear first-use option revolves around the concept of a "splendid" nuclear first strike—a nuclear counterforce attack intended to destroy or disable the adversary’s nuclear capabilities before they can be used. A nuclear first strike is fraught with risk and uncertainty. The United States can never be absolutely confident in its ability to fully neutralize the nuclear threat in a disarming first strike, and the possibility that even one or two nuclear weapons could survive and be used in retaliation against the U.S. homeland or on U.S. allies should temper proposals for a first strike.
The problem of successfully executing a nuclear first strike becomes even more challenging if adversaries develop and deploy mobile and relocatable ballistic missiles. If intelligence were uncertain or incomplete regarding the exact location of an opponent's nuclear forces, the United States would have to use so many high-yield nuclear weapons as to make the potential benefits prohibitively risky and costly. Conversely, if intelligence is believed to be accurate and complete,ISnuclear weapons are unnecessary for attacking mobile targets, as conventional forces are capable of destroying (or at least disabling) mobile missile launchers.
Finally, nuclear weapons could be used to threaten hard and deeply buried targets (HDBTs). There are two reasons why nuclear weapons do not provide a militarily effective or politically feasible solution in this regard. First, there are sharp physical limits on the burrowing depth of any nuclear earth-penetrating weapon (EPW). EPWs cannot burrow deep enough to destroy targets buried well below ground, and adversaries can always dig deeper. Second, EPWs cannot penetrate deep enough underground to contain the blast and prevent fallout. Consequently, nuclear EPWs risk causing significant collateral damage, particularly from radioactive fallout. Given the well-known U.S. desire to avoid civilian casualties, adversaries could attempt to increase the disincentives of a nuclear EPW attack, such as locating strategic underground facilities in highly populated areas to ensure that a nuclear strike against an HDBT would cause maximum collateral damage.
The United States should therefore place primary reliance on other weapons and tactics to defeat HDBTs. Conventional EPWs are sufficient to reliably destroy relatively shallow targets, and the capabilities of conventional EPWs are increasing. In addition, the United States can employ "functional defeat" tactics to deal with HDBTs. For example, it could target the facility's power sources, communications lines, and entrances and exits. Another option is to capitalize on the accuracy of conventional EPWs by using multiple weapons to repeatedly strike the same spot, thereby "burrowing" down to the desired depth.
If a nuclear-armed opponent believes that the United States might use nuclear weapons first in a disarming strike, a severe crisis could be especially dangerous and unstable. A crisis is "stable" when neither side has an overriding incentive to use nuclear weapons first, and both sides are aware of this situation. Conversely, a crisis is "unstable" when one or both states have an overriding incentive to strike first.
Given U.S. quantitative and qualitative advantages in nuclear forces, and given that current and potential nuclear-armed adversaries are likely to have nuclear arsenals with varying degrees of size and survivability, in a future crisis an adversary may fear that the United States could attempt a disarming nuclear first strike. Even if the United States has no intention of striking first, the mere possibility of such a strike left open by a policy of not ruling one out could cause suboptimal decisionmaking in the heat of an intense crisis and increase the chances that nuclear weapons are used.
The U.S. option to use nuclear weapons first could generate crisis instability in three ways. First, in a severe crisis, intense apprehensions about a U.S. first strike could prompt an opponent to take measures to increase the survivability of its forces and help ensure nuclear retaliation, such as adopting a launch-on-warning posture, rapidly dispersing forces, raising alert levels and mating warheads to missiles, or pre-delegating launch authority to field commanders. These actions increase the possibility of an accidental launch or other miscalculations that could lead to unauthorized use.
Second, in the midst of an intense crisis, trepidations about a U.S. first strike could create incentives for signaling and brinksmanship that increase the chances of miscommunication and nuclear escalation. For example, concerns about a U.S. attack could prompt an adversary to take measures to decrease the vulnerability of its forces, such as mating warheads to delivery vehicles, fueling missiles, or dispersing forces. While the opponent might intend these measures to deter a U.S. counterforce strike by increasing the survivability of its forces, U.S. political and military leaders might misperceive these actions as a sign of the opponent's impending nuclear attack and decide to preempt.
Third, a state could be enticed to preempt out of fear that if it does not launch first, it will not have a second chance. A "use-it-or-lose-it" mentality might give an opponent a strong incentive to preempt. In this context, the adversary’s motivation to use nuclear weapons first comes not from the possibility of gaining some advantage, but rather from the belief that waiting and receiving what it believes to be a likely U.S. first strike would only lead to an even worse outcome.
For the United States and its allies, NFU has several military and political benefits. First, it would enhance crisis stability. A credible NFU policy would help decrease an opponent's trepidations about a U.S. first strike, thereby reducing the possibility that nuclear weapons are used accidentally, inadvertently, or deliberately in a severe crisis.
Second, NFU would give the United States a consistent and inherently credible nuclear policy. Although some states might question U.S. political resolve to use nuclear weapons first, adversaries cannot dismiss the possibility of a nuclear response after U.S. interests have been attacked with nuclear weapons. The threat to use nuclear weapons in response to a nuclear attack is highly credible, and it is a threat that U.S. political leaders should want to execute if deterrence fails.
Third, NFU could help assuage some of the recent criticisms of U.S. missile defense and nuclear stockpile maintenance initiatives. A credible NFU policy could help alleviate concerns that missile defenses might be used to complement offensive operations, such as providing a "safety net" for any remaining weapons launched in retaliation after a U.S. first strike against a state's nuclear capabilities. An NFU policy might also score political points with domestic opposition to efforts by the United States to update its aging nuclear stockpile. NFU could help ease domestic and international concerns that efforts to update and enhance the safety and security features of the U.S. nuclear arsenal might inadvertently signal that the United States views nuclear weapons as militarily useful.
Finally, NFU would provide the United States with important political benefits in its efforts to lead the nonproliferation regime and encourage greater international support for nonproliferation initiatives. Many nonnuclear member states of the Nonproliferation Treaty (NPT) often base their lack of support for U.S.-led multilateral nonproliferation initiatives on the grounds that the United States has not done enough to fulfill its obligation to Article 6 of the NPT, which commits the declared nuclear states to disarmament. Thus, NFU, by symbolizing an important step toward realizing Article 6, would help remove a significant roadblock to greater support for and participation in the NPT regime among nonnuclear NPT member states.
After sustained consultations with its allies, the United States should adopt an NFU policy. By foreclosing the U.S. option to use nuclear weapons first, NFU would enhance crisis stability, bolster conventional deterrence, and provide the United States with renewed political legitimacy and leverage as the leader of the global nonproliferation regime. If the United States is committed to reducing the role of nuclear weapons in its national security strategy, NFU should be at the top of the list of necessary changes to U.S. nuclear policy.
Department of Defense. Nuclear Posture Review Report. Washington, D.C.: U.S. Department of Defense, April 2010.
Drell, Sidney D., and James E. Goodby. What Are Nuclear Weapons For? Recommendations for Restructuring U.S. Strategic Nuclear Forces. Washington, D.C.: Arms Control Association, 2005, http://www.armscontrol.org/pdf/USNW_2005_Drell-Goodby.pdf.
Glaser, Charles L., and Steve Fetter. "Counterforce Revisited: Assessing the Nuclear Posture Review's New Missions," International Security 30, no. 2 (Fall 2005): 84–126.
Gormley, Dennis M. "Securing Nuclear Obsolescence." Survival 48, no. 3 (Autumn 2006): 127–148.
Nitze, Paul H. "Is It Time to Junk Our Nukes?" Washington Quarterly 20, no. 3 (Summer 1997): 97–101.
Sagan, Scott D. "The Case for No First Use." Survival 51, no. 3 (June/July 2009): 163–182.
Michael S. Gerson is a research analyst at the Center for Naval Analyses (CNA) in Alexandria, Virginia, where his research focuses on nuclear and conventional deterrence, nuclear strategy, and arms control. He is also cochair of the Next Generation Working Group on U.S.-Russia Arms Control. The views expressed in this article are those of the author and should not be taken to represent the views of CNA, the Department of the Navy, or the Department of Defense.
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Recommended citationGerson, Michael S.. “The Future of U.S. Nuclear Policy: The Case for No First Use.” February 2011