The author would like to thank Paul Davis, Mi-chael Gerson, Robert Jervis, Richard Brody, George Quester, the participants in the November 2, 2011, workshop on strategic stability, and especially Linton Brooks for their helpful and constructive comments on and critiques of this chapter. The views herein as well as any errors and omissions remain the author’s own and do not necessarily reflect the positions of any institution with which he is affiliated.
Strategic stability has been a stock in trade of dis-cussions about nuclear issues for over half a century.
Yet there has been little success in developing a con-sensus understanding of the concept that provides a meaningful framework for evaluating nations’ force postures and plans. This chapter seeks to draw from the long debate on the meaning and nature of the term to propose a concept of strategic stability that is con-crete and narrow enough to provide analytical clarity in judging nations’ nuclear forces while sufficiently comprehensive to be politically meaningful. In light of the proposed definition, the chapter will analyze in particular detail the strategic posture of the United States and provide recommendations for how to mod-ify it to conform more completely to this conception.
The Debate over Strategic Stability.
Strategic stability emerged as a concept during the Cold War as part of an effort to find a modus vi-vendi for the two hostile superpowers.1 Its basic logic was to stabilize the bipolar confrontation by ensuring that each side had the ability to strike back effectively even after an attempted disarming first strike by its opponent. This would give each party the confidence to wait even in the event of attack by the other party, while removing the obverse temptation to strike first to gain fundamental advantage. Thus the chances of war through the fear of disarmament or through the temptation to gain an advantage by attacking first would lessen.2
The core of the concept was “first-strike stability,”
defined at the end of the Cold War by Glenn Kent and David Thaler as a situation in an adversarial context in which, “after considering the vulnerability of strategic forces on both sides, neither leader perceives the other as pressured by the posture of forces to strike first in a crisis [and n]either leader sees an advantage in strik-ing first to avoid the potentially worse outcome of in-curring a first strike if he waits.”3 In simpler terms, a situation would be stable when both parties would see that massively launching first—whether to avoid being neutered or to try to disarm one’s opponent—
would be either unnecessary or foolish.4 The search for first strike stability therefore led to a focus on in-creasing the survivability of both U.S. and Soviet forces and command and control systems.5 To this end, both sides poured tremendous resources into ensuring the survivability of their systems and, more broadly, into ensuring their ability to retaliate.
A related idea was “crisis stability,” which was in the same genus as first-strike stability but focused on mitigating any pressures, including psychologi-cal ones, that would push a crisis towards spinning out of control. Supplementary to these concepts was the notion of arms race stability, the proposition that the costly and possibly deadly spiral of the arms race could be averted if each side’s arms developments were manifestly designed to conform to the enduring reality of mutual vulnerability rather than as plausible attempts to gain strategic superiority.6
Few disputed that minimizing first-strike instabil-ity was a worthy and important goal, but differences arose as to whether first-strike stability alone would suffice to guarantee a genuinely and meaningfully sta-ble strategic situation. Many argued that it would, see-ing the prospect of nuclear retaliation and escalation, however improbable, as sufficient to deter the West’s opponents, and worrying more that once the nuclear
“firebreak” was breached, Armageddon would too plausibly follow.7 They thus focused on eliminating any incentive to first nuclear use.8 Others, however, recognized that the obviation of any rational purpose for using nuclear weapons first could well undermine deterrence of old fashioned non-nuclear aggression, especially since it was the West that relied on the threat to escalate to nuclear use to compensate for the Soviet and Warsaw Pact superiority in non-nuclear arms.9 Those in this camp feared that an ambitious Moscow might doubt the West’s resolve and saw the limited use of nuclear weapons as both plausibly sensible and its threat as an important deterrent. They thus concen-trated on reconciling the effort to minimize pre-emp-tive or accidental nuclear war with a posture of dis-criminate nuclear use.10 Still others rejected the notion
of strategic stability entirely, seeing it as a dangerous delusion that would weaken deterrence.11 Skeptics of the concept and the proponents of the equation of sta-bility with eliminating incentives for first nuclear use did share one view, however—the United States could pursue strategic stability or it could pursue the capa-bility and affirm its resolve to use nuclear weapons first, but not both.12 Proponents of discriminate use, on the other hand, believed they could reconcile stra-tegic stability and first use.
These debates about whether strategic stability was a useful concept and, if so, what its definition should be were, unsurprisingly, never resolved, for they turned on differential assessments of risk, the sa-lience of rationality in crises, the aggressiveness and decisionmaking calculus of the Soviet foe, and other judgments not susceptible to definitive calculation.13 But the Cold War experience did appear to make some important things clear, most pertinently that the U.S.
role as security guarantor of key regions of the world, a guarantee underwritten by its nuclear force, stood in serious tension with the objective of removing any reason to resort to nuclear force, the objective implicit in a sole focus on reducing incentives for nuclear use.
Indeed, the observation was not lost on threatened allies that a too perfect stability at the strategic level could and perhaps did undermine U.S. nuclear um-brella guarantees, a point made with special force by those sheltering under that umbrella, such as German Chancellor Helmut Schmidt in the late 1970s.14 Conse-quently, while the U.S. Government came to embrace the pursuit of strategic stability, it consistently con-cluded after the late 1960s that a focus only on mini-mizing incentives to nuclear use would not suffice for
strategic attack, that in a situation of mutual assured destruction would be of only the most dubious ratio-nality, was seen as inadequate to deter the Soviets and assure U.S. allies. Rather, the United States needed to be able to retain not only the ability but also the resolve to use nuclear weapons first in a manner that was at least minimally rational and thus discriminate.16
These debates, while less salient than they were in the Cold War, have not ended, and are taking on re-newed importance as the U.S. margin of conventional military strength narrows in the face of the rise of Chi-na as a great power and the proliferation of nuclear arms and advanced conventional weapons.17 More to the point, major war among the major powers remains possible. Because of this enduring possibility, one that gives no evidence of disappearing, it is important that the United States develop and adopt a conceptual framework that enables it to pursue policies to protect it and its allies’ vital interests while minimizing the reasons for and chances of nuclear use. Given that the United States continues to shelter dozens of nations under its nuclear umbrella, including a number of states that have been quite insistent that Washington be prepared to use nuclear weapons on their behalf, these questions remain of the gravest import.18
A Definition of Strategic Stability: No Incentives for Nuclear Use Save For Vindication
of Vital Interests.
In light of these developments, it is important to develop a conception of strategic stability that can both minimize the chances of major war, including nuclear war, among the great powers while also ensuring that the United States is able to fulfill its extended
deter-rence objectives. Such a conception should be able to provide an analytical basis for determining, in the context of relations with those states with which the United States has accepted a relationship of strategic stability, whether each nation’s force posture conduces to stability.19 Logically, nations with which the United States must accept a stability relationship are those that, even in the wake of an attempted U.S. disarming first strike, can deliver a devastating nuclear blow against the United States itself. Today and for the foreseeable future the nations that fall into this category are Rus-sia and China.20 That said, such a conception should also be flexible and adaptable enough to extend to ad-ditional states should the United States come to accept such a relationship with additional powers, though such an extension seems neither likely nor necessary for the time being. Moreover, substantial elements of the conception’s logic should be able to apply to states with which Washington emphatically does not accept a stability relationship. For instance, even with states that Washington seeks to overpower, there should be no reason to go to nuclear war accidentally.21
To begin with, a worthy conception of strategic stability must incorporate the basic goods contained in the notion of first-strike stability. But first-strike sta-bility cannot alone suffice to create genuine stasta-bility.22 There are two reasons why first-strike stability alone is inadequate.
A thoroughgoing elimination of incentives to use nuclear weapons first would undermine the goal of deterring major war in general, since a unitary focus on ensuring that nuclear weapons are not used would, to the extent it was successful, perforce lead to a cor-relatively lesser degree of risk in the initiation of
sub-gically stable” because no one would ever dream of using nuclear weapons first, then no one would need to worry about conventional conflict—especially rela-tively limited conventional conflict—leading to nucle-ar escalation. In effect, to reach a situation of strategic stability would be to undo the “nuclear revolution”
and thus destabilize the sub-strategic level, since it would cordon off the deterrent effects of nuclear weapons.23
Second and more realistically, however, such a cordoning off could never truly succeed. But it could be perilously deceptive, actually increasing the chanc-es not only that war would start, but also that such a war would involve the use of nuclear weapons. This is because, while a pursuit of this conception of stra-tegic stability could never guarantee that an opponent would not use nuclear weapons first, the pretense that it could or had might well dull the potential attacker’s sensitivity to the tremendous risks of crossing an ad-versary’s red lines with non-nuclear forces.24 A nation possessed of a too complacent view that first-strike stability had marginalized nuclear weapons could well believe that it could press an advantage and cross an opponent’s red lines with non-nuclear forces, bra-zenly relying on the alleged stability at the strategic level to obviate the threat from the adversary’s nu-clear forces. This could trigger the defending party’s use of nuclear weapons. For, even in a situation of first-strike stability, the threatened party could sensi-bly use nuclear weapons, especially if the asymmetry of stakes favored the defense, gambling—potentially reasonably because of the favorable balance of resolve for the defense and the existence of a situation of mu-tual vulnerability—that the other side would not re-ply with a total strike.
In other words, just because one nation believes in marginalizing nuclear weapons does not mean oth-ers do—in the blunter terminology of Leon Trotsky, you may not be interested in nuclear weapons, but they may be interested in you. This reality is evident in the fact that at different times both Americans and Russians have emphasized nuclear forces for deter-rence of conventional aggression over the past 60 years. Nonetheless, this temptation to believe nuclear weapons can be marginalized is especially potent for Washington, which today enjoys an impressive, albeit probably declining, margin in conventional military force and has trumpeted the virtues of the tradition of nuclear nonuse.25
Thus, as crucial as concerns about minimizing the pressures towards pre-emption and accidental war based on an incorrect belief that an attack is in progress are, strategic stability cannot be solely about minimiz-ing incentives to use nuclear weapons. Rather, if the concept of strategic stability is actually to contribute to a genuine stability between potential adversaries, it must incorporate rather than implicitly exclude the ways in which nuclear weapons deter not only mas-sive nuclear attack, but also other forms of aggression against a nation’s core interests. A useful conception of strategic stability must, then, seek to minimize or eliminate fundamentally immaterial or peripheral incen-tives to using nuclear weapons first, while preserving and even validating those incentives to use nuclear weapons that are essential for effective deterrence, and thus genuine stability. Such a framework must indicate not only the ways in which nuclear weapons should not be used, but also those ways in which their use would be legitimate.
In this light, strategic stability should be under-stood to mean a situation in which no party has an incentive to use nuclear weapons save for vindication of its vital interests in extreme circumstances. While one cannot define the precise nature of “vindicate,”, the essence of the concept is that the only reason a nation should see sufficient reason to use nuclear weapons is in response to major aggression against its estab-lished, well-understood, and reasonably conceived vital interests.26 Terms like “major aggression,” “rea-sonably conceived,” and “extreme circumstances”
cannot be neatly defined and delineated, given the inherently shifting and contingent nature of politics, but the essence of the phrase is that nuclear weapons should only be used in dire scenarios in which a party finds itself under grave pressure from significant at-tacks that do not offer reasonable alternative means of redress.27 From this standpoint, the U.S. 2010 Nuclear Posture Review’s confining of threatened first use to
“extreme circumstances” involving itself or its allies satisfies this criterion.28 So, too, would Russia’s stated policy of narrowing its threat of first use of nuclear weapons to contingencies in which the survival of the Russian state is in jeopardy.29
In a strategically stable situation, then, a nation would see neither need nor incentive to use nuclear weapons except to make clear to an opponent that he had crossed a most vital red line with the probabil-ity that he would suffer further—and perhaps cata-strophic—loss if he continued his aggression. Incor-porating the important traditional conception of first strike stability and predicated on the assessment that vulnerability to some degree of nuclear retaliation is a given, fears of disarmament or decapitation on the one hand and ambitions for military advantage through
a disarming strike on the other would have little to no place. Rather, in the beau ideal of this conception nuclear weapons would become essentially purely political weapons, instruments of violent signaling and a terrible indicator of the willingness to escalate to levels of gross destruction.30 Naturally, no sharp distinction can be drawn between the domains of the
“political” and the “military,” but the point would be to narrow the purposes of employment of nuclear weapons down to its deterrent essence by subordinat-ing military objectives to broader political aims.31 The use of nuclear weapons in this fashion could—and generally speaking should—involve a military pur-pose, but this military purpose would be embedded in, oriented towards, and limited by broader political objectives. Such nuclear strikes would demonstrate a party’s willingness to inflict grievous cost on an op-ponent, to threaten more such strikes, and to run the risk of general war in order to persuade him of the folly of his aggression and the necessity of terminat-ing the conflict on grounds acceptable to the defend-ing party.32
By stripping away the essentially accidental as-pects of a nuclear deterrent relationship to its core of bargaining through the infliction of pain and the ma-nipulation of fear, this conception of strategic stability would be a crystallization, a refinement to its essence, of nuclear deterrence. Nuclear weapons would, like Samuel Johnson’s gallows, concentrate the minds of an opponent’s leadership, ensuring that there could be no misunderstanding of the strength of one’s re-solve to escalate and to risk general war. Such an un-derstanding of strategic stability would encompass the essential concerns of first-strike stability in
mini-that some uses of nuclear weapons must be valid for real stability to endure. In a stable situation, then, major war would only come about because one party truly sought it, not because of miscalculation. Given the nature of the nuclear revolution, this should make major war ex-ceedingly unlikely.33
If nuclear use would only be acceptable for vindica-tion of vital interests, though, what types of use would be appropriate? Because the point of strategically stable nuclear use would be to de-escalate a spiraling conflict on satisfactory terms, such uses would need to be limited, discriminate, and evidently restrained, designed to demonstrate both resolve and the willing-ness to escalate further as well as the readiwilling-ness to re-strain further use. The point of nuclear use under this conception of strategic stability would definitively not be to attempt to break out of a situation of mutual vulnerability, given such an effort’s toxic combination of futility and dramatic escalatory impetus, but rather to signal to an opponent that he had transgressed a most vital interest, to demonstrate one’s resolve about climbing the imperfectly controllable ladder of escala-tion, and to inflict pain on the opponent to attempt to dissuade him from pursuing his course of action.
Discriminate options would play a particularly im-portant role in this conception of stability, essentially as mechanisms for insisting upon war termination.
Since the effectiveness of nuclear deterrence rests ul-timately on the prospect of tremendous damage that outweighs any meaningful political end, the most ef-fective nuclear threats must connect to the credible possibility of such devastation resulting from trig-gering them. The essence of stabilizing nuclear use, then, is the demonstration of the willingness to begin mounting the inherently uncertain ladder of nuclear
escalation towards large-scale war while also offering the opponent the chance to agree to terminate the con-flict. But, since escalation to large-scale nuclear war
escalation towards large-scale war while also offering the opponent the chance to agree to terminate the con-flict. But, since escalation to large-scale nuclear war