As the Obama administration contemplates further changes to US nuclear policy and posture in its second term, it will no doubt encounter opposition from those who argue that the world is too dangerous and complex to permit further reductions in US and global nuclear force levels. Critics will make many assertions in support of their case, but two claims in particular are likely to underpin their defense of the status quo. The first is that nuclear weapons promote peace and the second is that more reductions by the United States and Russia are unlikely to strengthen the global nonproliferation architecture.
These arguments go to the heart of the debate about the meaning of nuclear deterrence and the appropriate role of nuclear weapons. They have been debated for decades, and we're likely to go on debating them for as long as nuclear weapons exist. Yet the answers will remain the same: The war-prevention benefits of nuclear weapons are overstated, and there are important links between disarmament and nonproliferation.
Nuclear weapons prevent war between great powers. This is one of the most common arguments made in support of nuclear weapons. For example, in a recent op-ed, Maj. Gen. William Chambers, the Air Force's assistant chief of staff for strategic deterrence and nuclear integration, claimed that nuclear weapons have created "a stability that prevented the deaths of tens of millions of civilians in wars between great powers that did not occur."
Nuclear weapons probably have had a moderating influence on the behavior of great powers. The final report of the International Commission on Nuclear Non-Proliferation and Disarmament, noted that "it is hard to contest the almost universally held view that the absence of great power conflict since 1945 must be at least in part attributed to the fear of nuclear war." Yet, while it is true that large-scale war has been avoided and that nuclear weapons may be one of the causes, it is not at all clear that the bomb has been the necessary factor. It is worth noting that nuclear weapons have not prevented all types of war or conflict. Non-nuclear armed Egypt and Syria attacked nuclear-armed Israel in 1973, and India and Pakistan have fought one another since acquiring nuclear weapons.
Whatever one thinks about the role of nuclear weapons in preventing great power war during the Cold War, these benefits appear to be less relevant in the 21st-century threat environment. As nuclear proliferation expert George Perkovich argues:
Aside from nuclear weapons themselves, the threats facing the US and its allies today and in the foreseeable future are not of the scale and type that nuclear weapons are either necessary or credible to deter. … The more realistic problem is to deter adversaries from smaller scale thrusts to enforce territorial claims or extort diplomatic concessions, and to deter terrorism, cyber attacks, energy supply blackmail, etc.
Moreover, the Cuban Missile Crisis and other brushes with disaster during and since the Cold War demonstrate that nuclear deterrence is not foolproof. It is susceptible to misperception, miscalculation, technical failure, or accident. The use of nuclear weapons is possible even if no one desires such an outcome, especially during a grave crisis in which military forces are on high alert, nuclear doctrines emphasize preemption and escalation control, accurate information is hard to get, and events on the ground cannot be controlled.
The alleged war-prevention benefits of nuclear weapons, then, are often overstated and must be weighed against the danger that they will be used, a risk that is exacerbated by the presence of the bomb in some of the most unstable regions of the world and the threat that proliferation and nuclear terrorism will lead to more frequent and complex conflicts and nuclear crises in the future.
There is no connection between nuclear disarmament and nonproliferation. The corollary to this argument is that US nuclear weapons prevent proliferation by undergirding (or extending) US nuclear security guarantees to allies, without which these allies may be tempted to acquire their own nuclear weapons. These claims are flawed for several reasons.
First, there clearly is a connection between nuclear disarmament and nonproliferation: It is a link that is established in the Nuclear Non-Proliferation Treaty (NPT). The NPT commits the five states that possessed nuclear weapons when the treaty opened for signature in 1968 (the United States, the Soviet Union, China, Great Britain, and France) to give up their nuclear weapons. In addition, it obliges the other state parties (the non-nuclear weapon states) not to acquire nuclear weapons, but it does not prohibit them from pursuing civilian nuclear power programs outside the treaty. It is difficult to fathom that the non-nuclear weapon states would have agreed to extend the NPT indefinitely in 1995 if the nuclear weapon states had insisted that they were not obligated to disarm.
The 2009 final report of the bipartisan Congressional Commission on the Strategic Posture of the United States, which included such conservative stalwarts as Keith Payne and former Defense Secretary James Schlesinger, also pointed to a linkage. While the report was skeptical "that unilateral nuclear reductions by the United States would have any positive impact on countries like North Korea and Iran," it observed that other "nations may not show the nuclear restraint the United States desires or support nonproliferation efforts if the nuclear weapon states take no further agreed steps to decrease their reliance on nuclear arms."
In a recent article analyzing disarmament and nonproliferation, Jeffrey Knopf, program chair of the Monterey Institute's Nonproliferation and Terrorism Studies, concludes "that in some, but not all, cases either a direct or indirect linkage will be a factor in a nonnuclear state's decisionmaking." Consequently, steps by nuclear weapons states to reduce the role and number of nuclear weapons "should help to strengthen the nonproliferation regime even though they will not be a cure-all for every ailment confronting it."
Second, US nuclear policies and posture also impact the nuclear policies and posture of other nuclear-armed states. For example, it is widely recognized that China will not ratify the Comprehensive Nuclear Test Ban Treaty until the United States does. Likewise, US efforts to develop and improve long-range missile defenses could undermine US relations with Russia and China. As the Strategic Posture Commission noted, "[D]efenses sufficient to sow doubts in Moscow or Beijing about the viability of their deterrents could lead them to take actions that increase the threat to the United States and its allies and friends."
Third, so long as US allies could fall victim to nuclear attack, the United States should retain nuclear weapons to deter such an attack. However, the claim that US nuclear reductions could prompt allies such as Japan, South Korea, or Turkey to acquire their own nuclear weapons understates the domestic and international political costs of acquiring nuclear weapons and mischaracterizes that nature of extended deterrence. The continued maintenance by the United States of thousands of nuclear weapons is not necessary to deter the nuclear threats its allies face today. Commitment is illustrated first and foremost by the strength of shared political and diplomatic relations. The United States should work closely with allies to strengthen common interests as a demonstration of its resolve to protect them.