Policy Memos

Keeping the “New Cold War” Cold: Nuclear Deterrence With U.S. and Russian Nuclear Force Modernization

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(PONARS Policy Memo) After two decades of dramatic reduction and deliberate neglect, the nuclear arsenals that were at the center of security relations between the Cold War superpowers are reaching the ends of their operational lives. Rather than allow age and obsolescence to erode their nuclear capabilities and carry us into a post-nuclear era, both Russia and the United States chose to modernize and redevelop their nuclear arsenals with new weapons systems, platforms, and strategy. For those raised during the Cold War, this can be a terrifying prospect.

Yet, both the fears and the advantages of the new weapons are overstated. The U.S. and Russian nuclear doctrines reflect a newly adversarial relationship, but the development of new weapons and doctrines for their use need not be destabilizing. Both doctrines are status quo oriented and primarily defensive. They are designed to deter potential aggressors—not to “roll back” rivals, overturn governments through military conquest, or to expand influence. Both are consistent with achieving a certain “strategic stability” or a stable mutual deterrence. At the same time, there is no technical military solution to the conflicts of interest and the ambiguity of resolve that characterized key U.S.-Russian interactions after the Ukraine crisis. Enhancing nuclear capability does not necessarily enhance deterrence, let alone security. If security is to be achieved it will have to address specific conflicts in relations between the two states.

A Changing Relationship Requires a Changed Force Posture

The past decades have made clear that force postures and our sense of security, follows—in part, at least—from underlying international political relationships. In the first decade following the end of the Cold War, there was a clear recognition that the U.S.-Russian relationship had changed fundamentally from its Cold War nadir even if the weapons platforms of the Cold War persisted. The two countries were no longer fundamental adversaries. The threat of surprise nuclear attack diminished to the point of implausibility. Whatever your preferred Cold War metaphor—the two gunfighters standing off against one another, two scorpions locked in a bottle, or two cars playing chicken—it no longer reflected the strategic relationship between Russia and the United States. The two countries signed arms control treaties, re-targeted their nuclear weapons, and reduced, mothballed, or eliminated their cold war nuclear arsenals. Through the Intermediate Nuclear Forces (INF) treaty, START, New START, and unilateral decisions to retire nuclear weapons systems (such as the U.S. arsenal of submarine-launched nuclear cruise missiles), the number and variety of nuclear weapons was reduced dramatically.

By the mid-2000s, the existing nuclear weapons systems inherited from the Cold War began to reach the end of their shelf life. Even if the plutonium “pits” to trigger nuclear devices proved to be fairly robust (with a potential lifespan of close to a century), the nuclear warheads and delivery systems were aging. The electronic systems used to command, control, and guide strategic nuclear forces were decades old and approaching the point where they were no longer reliable and secure. As a result, over the past decade, the governments of both Russia and the United States faced the question of whether and/or how to craft a security strategy and build a nuclear arsenal for the contemporary international environment.

Following the Ukraine crisis of 2014 and the Russian annexation of Crimea, the post-Cold War relationship between the United States and Russia—a relationship that led both sides to walk back from a nuclear threat—has definitively come to an end. The most recent Russian and U.S. strategy documents make clear that they perceive one another as adversaries (perhaps even the primary adversary), and characterize the current international environment as threatening with a relatively high level of geopolitical competition among established and emerging powers. Their proposed nuclear force postures and strategies reflect this change.

Many have sounded the alarm over these choices made by Moscow and Washington. In particular, some have raised concerns that by developing new low-yield non-strategic nuclear weapons and doctrines for their use, both Russia and the United States are lowering the threshold for the use of nuclear weapons in conflict and increasing the likelihood of nuclear war. Others argue that the new capabilities will signal a greater resolve on the part of the two countries, thereby deterring aggressive actions and preventing the escalation of limited regional wars to a nuclear conflict.

What Is Strategic Stability and How Do We Achieve It?

An adversarial relationship need not be an unstable one. Both sides refer to a desire to achieve “strategic stability.” This is potentially encouraging, but what does it mean? In a Cold War context, “strategic stability” meant having a devastating “second strike” capability. The essential pillar of stability was the notion that nothing could be gained from initiating a nuclear strike because the response would be devastating and certain—a form of deterrence through threat of punishment. Any weapons that diminished the certainty of the second strike—either by undermining the survivability of nuclear forces or by diminishing their effectiveness (e.g., missile defenses)—were seen as undermining strategic stability.

When current Russian officials claim that the development of missile defenses or long-range precision strike capability undermines strategic stability, it is this Cold War notion of a secure second-strike capability that they have in mind. They understandably do not wish the United States to have the ability to eliminate their strategic arsenal in a surprise counterforce strike, or to pick off the remaining missiles from a potential retaliatory strike in a way that would render the losses from a war between the two countries to be tolerable to the United States. The United States similarly seeks to maintain a robust second-strike capability through the traditional triad.

But a secure second-strike capability is not the only, or even necessarily, the most effective, form of deterrence, particularly for the regional conflicts that seem most likely to escalate to great power wars. For both the United States and Russia, the operative scenario for great power conflict is the escalation of a smaller-scale conventional conflict on the boundary between Russia and NATO. This is the scenario that was the basis for the most recent (2017) Zapad military exercises. The 2018 U.S. Nuclear Posture Review (NPR) suggests the need to deter lower-level regional conflicts and prevent Russia from perceiving that it can obtain positive results by threatening (or engaging in) limited nuclear escalation. Both sides are developing strategies and nuclear capabilities to facilitate (or dominate) escalation following an attack on an ally. This is, in principle, a good thing. To the extent that a NATO intervention in Belarus or a Russian intervention in Estonia are both credibly assumed to escalate to a nuclear exchange, those outcomes are more likely to be avoided. So long as neither side feels that the initiation of an attack will achieve strategic objectives at an acceptable cost, deterrence is likely to be stable. Neither side will perceive an opportunity for aggression based on the limited capabilities or resolve of the other. Strategic stability will be obtained.

The NPR makes this intent quite explicit. Its most controversial recommendation—to develop new low-yield non-strategic nuclear weapons—is explicitly designed to eliminate what the U.S. perceives to be an adversary’s advantages in limited (regional) war:

“Expanding flexible U.S. nuclear options now, to include low-yield options, is important for the preservation of credible deterrence against regional aggression. It will raise the nuclear threshold and help ensure that potential adversaries perceive no possible advantage in limited nuclear escalation, making nuclear employment less likely.”

Stable deterrence is maintained by the United States (and Russia) having the capability and resolve to engage in “nuclear war-fighting” in a way that would impose sufficient costs on the aggressor to prevent it from initiating such a conflict in the first place.

Arms “Management” or Arms Control, but Not Necessarily Arms Limitation

To some extent, this version of “strategic stability”—defined as the avoidance of great power conflict through effective, credible mutual deterrence—can be attained without international arms treaties or agreements. Indeed, it may even be enhanced by allowing some provisions of existing treaties to lapse or be revised. Limiting capabilities or the sizes of nuclear forces is not nearly as important as making sure that the costs of aggression are unacceptably high. We should not cling to existing agreements like a security blanket, nor see violations as a precursor to international aggression, but as a response to a potentially changed security environment.

But even in this adversarial environment, there is some scope for cooperation. There is no question that deterrence is more stable when the capabilities, intentions, and resolve of the adversaries are clear and transparent. One of the positive side-effects of the arms limitation treaties has been the degree of transparency they have afforded through interaction and regular monitoring. No one wants a launch misperceived, and neither side has an incentive for their capabilities or resolve to be underestimated.

Relationship Management and Threat Reduction

Ultimately, the likelihood of great power conflict—or a war between U.S. and Russian forces—depends far more on avoiding or managing direct conflicts of interest. We can work on that directly, but it requires a degree of mutual awareness of political interests and motivations of potential rivals.

Here is where both U.S. and Russian strategic doctrines (and the policy communities that generated them) fall short. Stability is not a technical problem with a technical solution. Having an arsenal of low-yield nuclear weapons does not signal “resolve” as the NPR seems to suggest. Capabilities are not resolve. The differences in resolve and the intensity of U.S. and Russian interests in Ukraine, for example, is what determines how each side is willing to escalate. And the willingness to use nuclear weapons in such a conflict would not depend on the yields. In conflicts where neither country has a vital interest, it is not clear what would indicate resolve or how far each side would be willing to go in a direct conflict—and that uncertainty is dangerous. Those dangers are not stabilized by a more “usable” non-strategic nuclear arsenal.

Which brings us to the crux of the matter: The modernization of nuclear forces in the United States and Russia is a response to a more hostile security environment, but it does not address the conditions that generate that hostile security environment. It is good, of course, that both Russian and U.S. strategic documents are realistic about the existence of tensions. It is a not a world in which we can let nuclear weapons go away, and we should recognize that past U.S. policy, in particular, was predicated on assumptions about the declining tensions that have been proven to be false.

However, it is not good--indeed it is destabilizing--that neither side seems to acknowledge the role of their own actions in generating the tensions or the opportunities for defusing them. On the Russian side, the leadership appears to work from a Cold War caricature of the inherently messianic and expansionist nature of U.S. power. There is no acknowledgment that the annexation of a neighboring state’s territory and the commitment to defend those annexations with nuclear weapons could be seen as a threatening precedent. Nor does there appear to be any perception that cyber attacks, assassinations, or influence operations within the United States or Europe would be considered unacceptable new forms of aggression or intervention.

On the U.S. side, the NPR seems to have no awareness of what motivates Russian actions, nor that the challenging geostrategic environment and renewed great power competition is partially a product of U.S. actions and choices. The document presents a caricature of Russia’s “destabilizing” policy as a source of the changed threat environment, but Russia’s aggressive actions are not emerging from a vacuum. In Ukraine, Russia’s most populous and powerful neighbor to the West, Russia saw a freely-elected president overthrown only a year from a scheduled presidential election, and an anti-Russian, pro-NATO government put in his stead. All done with the apparent blessing of the United States. In Syria, the United States has never articulated a realistic vision of a post-Assad Syria consistent with U.S. interests, but we consistently advocated the overthrow of the Assad regime. The Russians see U.S. policies as destabilizing, and understandably so.

Ultimately, the drivers of conflict between Washington and Moscow need to be worked on directly. There is no technical fix to the problems in the U.S.-Russian relationship, and far more can be done to defuse conflict between the two countries rather than be placed in the position of having to rely on a nuclear deterrent, especially given the persistent uncertainty about the conditions under which each country would be willing to use nuclear weapons. A central element of minimizing the security dilemma and dangerous escalatory cycles is an awareness of how one’s own state’s actions will be perceived by adversaries. To the extent that policies do little to enhance one’s own security interests but pose a significant threat to rivals, they should be avoided. Transparency of actions, capabilities, and intentions—perhaps achieved through the type of bilateral and multilateral engagement that is increasingly being curtailed by both sides—could contribute to a lessening of tensions or at least a clarity of interests and ambitions that would make nuclear deterrence less necessary.

Keith Darden is Associate Professor in the School of International Service at American University.



About the author

Associate Professor (School of International Service)
American University