One of the strongest arguments in favor of nuclear weapons is deceptively straightforward: states need nuclear weapons to ensure their survival in a dangerous world. By threatening to inflict incalculable horrors on the combatants, nuclear weapons can make war prohibitively costly and prevent it from occurring. For no benefit that a state might seek by waging war, regardless of how important it might be, could possibly outweigh the catastrophe of nuclear devastation. According to this logic, halting the spread of nuclear weapons across the globe, or disarming states that already possess nuclear weapons, could actually be counterproductive, as it would make conflict safer and therefore more likely. Nuclear weapons thus represent an awful bargain, in which nuclear states accept a small likelihood of calamity in order to avoid conventional war. But given the high cost and frequency of conventional conflict in a non-nuclear world, it is a bargain worth making.
This pro-nuclear argument presumes the existence of a close relationship between nuclear weapons and deterrence. The nuclear bargain is acceptable only because nuclear weapons are highly effective deterrent tools, more effective than any other means that states have at their disposal. If this assumption of a tight linkage between nuclear weapons and deterrence were in fact incorrect, it would change the contours of the debate, and the nuclear bargain outlined above would seem far less attractive.
Scholars skeptical of nuclear weapons’ stabilizing effects have long sought to problematize their presumed tight link with deterrence. Some have focused on the organizations that controlled nuclear weapons, arguing that they would commit errors that would undermine nuclear weapons’ deterrent effects. For example, militaries would devise standard operating procedures for managing the weapons that increased the likelihood of accident. Or they would permit military officers to adopt the destabilizing, offensive nuclear strategies that they would tend to prefer, but that could also lead to the outbreak of conflict. This argument did not deny the existence of a tight logical link between nuclear weapons and deterrence. The argument claimed, rather, that in practice, organizational pathologies would short-circuit the nuclear weapons-deterrence connection, preventing states from adopting the cautious, stabilizing policies that they might otherwise have embraced in a nuclear environment.
A second major approach to decoupling nuclear weapons from deterrence directly addressed the logical link between the two. Unlike the “organizational” argument outlined above, this “strategic” approach maintained that nuclear weapons could increase the likelihood of war not because of bureaucratic pathologies, but because of decision-makers’ rational calculations regarding nuclear weapons’ coercive utility. A state that was dissatisfied with the status quo, and militarily weak relative to its adversaries, could be emboldened to challenge existing territorial or political arrangements through military action that it would have deemed excessively dangerous in a non-nuclear environment. This would occur because of nuclear weapons’ ability to insulate the weak state from its adversary’s conventional superiority; the stronger state, fearing nuclear escalation, would refrain from retaliating against the weak state’s provocations with the full weight of its conventional capabilities. Thus, nuclear danger could actually create incentives for rational policymakers to choose to engage in aggressive behavior. This meant not only that nuclear weapons might not generate deterrence in practice. It meant that nuclear weapons could fail to generate deterrence because the two were logically opposed to one another.
This volume takes an eclectic approach to problematizing the relationship between nuclear weapons and deterrence. In the opening chapter, Benoit Pelopidas advances both of the above arguments. He explains that organizations can short-circuit rational nuclear decision-making, leading to accidents and conflict. He also notes that nuclear weapons can create incentives for aggressive behavior by rational decision-makers. In addition, the chapter advances a number of other arguments that do not fall neatly into either of the above schools. For example, it highlights the issue of historical uncertainty, pointing out that we do not actually know why past cases that are often cited as successful examples of nuclear deterrence either remained peaceful or did not escalate. Close examination of these cases suggests that nuclear weapons may not have been responsible for their favorable outcomes. The chapter also emphasizes the possibilities for what one might call “nuclear substitution,” generating deterrence through the use of tools other than nuclear weapons. As Pelopidas points out, conventional weapons systems can, in some cases, protect states as well as or better than nuclear weapons, without subjecting them to nuclear weapons’ costs and dangers. Indeed, in a variety of situations, nuclear weapons may simply be inappropriate to security challenges that a state faces. This volume thus seeks to show that, for a wide range of theoretical, empirical, and practical reasons, nuclear weapons and deterrence should be decoupled from one another.
If this approach is correct, and states really can decouple nuclear weapons from deterrence, one of the most important arguments against nuclear arms control is considerably weakened. This creates new possibilities for states either to undertake serious reductions in their nuclear arsenals or to forgo nuclear weapons entirely. For, by doing so, states will not necessarily forfeit the deterrence that they need to survive. Indeed, doing so may actually help states to avoid deterrence failure and to protect themselves more effectively from the dangers of a violent and competitive world.
Even if nuclear weapons and deterrence can be decoupled in principle, however, achieving such an outcome could be difficult in practice. Decision-makers might fail to recognize security organizations’ propensity for mismanaging nuclear weapons; might not understand that nuclear weapons can create incentives for aggressive behavior; might not know that the historical evidence linking nuclear weapons and deterrence is tenuous; might not realize that they could generate deterrence using non-nuclear tools; or might want nuclear weapons for reasons unrelated to deterrence. In any of these scenarios, the nuclear-deterrence decoupling outlined above would have limited relevance for real-world policymaking. It is also possible that decoupling logic could have an impact in one region of the world, where decision-makers recognize the tenuousness of the relationship between nuclear weapons and deterrence, but be irrelevant in another, where leaders still believe that nuclear weapons and deterrence are logically or practically connected, or want nuclear weapons for reasons unrelated to deterrence. The real-world applicability of decoupling logic must therefore be examined on a case-by-case basis.
South Asia is an important area in which to assess the applicability of the nuclear decoupling approach. It is one of the world’s most volatile regions. India and Pakistan have fought four wars and engaged in innumerable skirmishes in the roughly six decades since independence. Their relations remain highly antagonistic. And the two countries possess sizable nuclear arsenals. If a decoupling of nuclear weapons from deterrence could lead to significant Indian and Pakistani nuclear reductions, it would thus make the region and the world considerably safer. This chapter attempts to determine the potential for nuclear decoupling to do so.
I argue that South Asia does not offer a single answer to this question; Indian and Pakistani positions regarding the relationship between nuclear weapons and deterrence diverge significantly. In the Indian view, deterrence and nuclear weapons are not wholly synonymous. Indian leaders not only believe that nuclear weapons can fail to deter conflict, but realize that nuclear weapons can actually encourage aggressive behavior that leads to the outbreak of conflict. They also recognize that, in certain situations, conventional capabilities can generate deterrence more effectively than nuclear weapons. Finally, Indian leaders value nuclear weapons’ political symbolism and believe that they hold considerable value even apart from their deterrent effects. Nonetheless, the Indians also value what they view as nuclear weapons’ robust deterrent characteristics, which they believe can protect them from stronger powers such as China. As a result, the Indians will not merely maintain their existing nuclear capabilities for the foreseeable future—they plan to augment them both qualitatively and quantitatively. Thus India is a mixed case. Indian leaders do not entirely conflate nuclear weapons and deterrence, but do believe that nuclear weapons’ deterrent effects can help to ensure their security against particular dangers.
Pakistani leaders, by contrast, believe that deterrence and nuclear weapons are very closely linked. The Pakistanis are convinced that, just as nuclear weapons helped to prevent a Warsaw Pact conventional attack against weaker NATO during the Cold War, Pakistan’s nuclear capacity has historically prevented aggression by a conventionally stronger India. They also believe that, in the absence of a robust nuclear capability, Pakistan will be unable to generate sufficient deterrence in the future to protect itself from a growing Indian conventional threat. As a result, the Pakistanis plan to rely even more heavily on nuclear weapons in the future than they have previously, lowering the nuclear threshold on the subcontinent in order to deter a catastrophic Indian conventional attack.
Although the differences between Indian and Pakistani understandings of the relationship between nuclear weapons and deterrence are real, one should not overstate their significance. For, at bottom, the practical reality for both countries is similar. Despite divergent views, neither side is going to eradicate or significantly reduce its nuclear weapons capacity in the foreseeable future. In fact, both sides are increasing their nuclear capabilities—though they are doing so in ways, and for reasons, that are quite different from one another.
Editor's note: This essay is part of a series of pieces about nuclear deterrence that Defining Ideas will be publishing in the weeks ahead. All of the essays are and will be from the new Hoover Press book, The War That Must Never Be Fought. To continue reading this essay, click here.
S. Paul Kapur is a professor in the National Security Affairs Department at the US Naval Postgraduate School. The views that he advances in this article are solely his own and do not necessarily reflect those of the Department of Defense or any other government agency.