A bimonthly magazine on international affairs, edited in Germany's capital

The Comeback of Nuclear Deterrence

A “101” on interests, irrationality, inherent sense, inevitability – and on buying time.

Nuclear deterrence may once more be necessary – but the tools once used to implement it have rusted. Consider this a refresher course for what the West will need to do to re-establish a deterrence regime.



Nuclear deterrence is back. After two decades of neglect, the concept is re-entering the security narrative of the West. Russia’s “nuclearized” rhetoric, along with its actual nuclear deployments, may have been the prime cause for the renaissance of nuclear deterrence, but the dangers of a nuclearized Middle East and a new arms race in Asia are hardly less worrisome. All these developments point in the same direction: the West will need to reaffirm nuclear deterrence as an important element of its broader security strategy.

Alas, restoring nuclear deterrence to its rightful place is easier said than done. Since the end of the Cold War, interest has waned. The focus shifted towards scenarios where nuclear deterrence did not matter: the fight against terrorism and military interventions in failing states. Consequently, the understanding of deterrence and the policies and instruments used to implement it has atrophied.

Worse, in trying to make the case for nuclear abolition, many analysts have sought to “debunk” nuclear deterrence as a “myth” over the past decade. These attempts to outsmart common sense never carried much intellectual weight, yet they managed to create a new “political correctness” that deters the successor generation from studying deterrence.

And study is urgently needed. As a basic principle of human interaction deterrence is easy to comprehend, yet its practical application in international relations is dependent on many factors that are often ignored. Above all, nuclear deterrence is not a panacea. It contains many paradoxes and pitfalls. Below are some elements that should be present in any “nuclear deterrence 101”.

It’s About Interests

Many people equate deterrence with military strength. But simply piling up military hardware will not do the trick: an aggressor may still attack based on a calculation of your interests and will rather than your capabilities. If it looks your interest in defending a certain objective (e.g. an ally) is low, your opponent will not be deterred. Yes, your nuclear weapons can obliterate theirs, but your opponent can be reasonably certain that you will not employ them except when vital interests are at stake.

In short, while the risk of things getting out of hand may induce a general sense of restraint in international affairs, in a crisis nuclear deterrence will only work at the “high end”. That’s why allies of nuclear powers constantly need to be reassured by their protector that it considers their security as truly vital. Or, as former British Defense Secretary Denis Healy aptly noted, during the Cold War it took only 5% credibility to deter the Soviet Union, but 95% to assure your own allies.

We’re Only Human

A stable deterrence regime requires all actors to adhere to a “rational” cost-benefit calculus. Thus, nuclear deterrence cannot work against actors that are “irrational” to begin with, e.g. fanatical martyrs. Deterrence may also fail when rationality evaporates in a crisis; certain ideologies or strains of nationalism, for example, may produce the kind of myopia that makes leaders adopt risky offensive strategies.

But the more important scenario in which rationality could disappear is essentially defensive. Since humans will always give priority to avoiding losses rather than to acquiring gains, the fear of losing something valuable will make leaders take far greater risks than the opportunity to change the status quo in their favor. Hence, as much as one would want to have the upper hand in a crisis, one should still avoid pushing a nuclear adversary into a corner.

Know Your Adversary’s Culture

Deterrence may be a universal concept, but its practical application may well be culture-specific. For example, a culture that attaches great value to sacrifice or even martyrdom will be much harder to deter with the specter of military punishment than a “post-heroic” society. This is not to say that certain states are “un-deterrable”, but their cost-benefit calculus might be so different as to render the defender’s deterrence messages ineffective. Hence, if you want your adversary to understand your deterrence message correctly, you need to have a fairly good grasp of their “strategic culture”: historical experiences, values, core beliefs, military traditions, and, last but not least, language. Despite your best efforts, you will never get it perfectly right – but you might not get it quite so wrong.

Try Seeing Yourself Through Your Opponent’s Eyes

The fundamental dilemma of nuclear deterrence is that it revolves around threats. Hence, what might look like a perfectly defensive deterrence posture to you may look like intimidation to others. Today’s Russia offers a perfect case study. Moscow’s current nuclear bluster may be a specific “Russian” way of upholding deterrence by making the country appear both powerful and fearless. However, as Russia’s neighbors are scared, they will revert to countermeasures that might well result in a net decrease of Russia’s security. To avoid such counterproductive outcomes, you must remain keenly aware that your political declarations, military exercises, and procurement decisions will be interpreted by your opponent in ways far more sinister than you might consider reasonable. Yes, you know that you are the good guy who would never do anything sinister, but your adversary thinks the same about themselves.

More May Not Always Be Better

Nuclear deterrence is a concept that has many built-in risks, but nevertheless makes inherent sense. That is why the majority of Western publics do not revolt against their respective nations’ security policies. However, the absence of large-scale public protest must never be mistaken for unshakeable support of nuclear deterrence. Alarmist rhetoric from an administration, loose talk from leaders, or the deployment of certain weapons systems can spark massive protests all the way to a major domestic crisis. That is why the military requirements for deterrence must be balanced with the need to reassure the public – and why, in some instances, not deploying potentially controversial military hardware may be the wiser choice. Always keep in mind that your deterrence message has at least two addressees: your opponent and your own population. The true art of deterrence is to impress the former without frightening the latter.

Talk Isn’t Cheap

Deterrence is not a substitute for dialogue with an adversary. Quite the contrary. Without communication between the antagonists, deterrence will not be the solution, but rather become the problem. To avoid misunderstandings and miscalculations a stable deterrence regime requires a degree of transparency and predictability. Put differently: deterrence requires rules and recognized “red lines”, however tacit. Herein lies the true value of arms control: while arms control talks have not delivered all that much “control”, it is the talks themselves that really mattered. They created a channel for a conversation on security matters of mutual concern that may have been far more important than the technical bean counting.

Deterrence Is About Buying Time

The return of nuclear deterrence is inevitable. In light of what appears like an increasing militarization of international relations, a Western soliloquy about global nuclear abolition looks increasingly out of touch with reality. Complacency, however, is something the West can ill-afford. With more countries obtaining nuclear and other weapons of mass destruction, deterrence will become increasingly necessary, but also more difficult. A multi-stakeholder deterrence system is even more prone to failure than the Cold War nuclear bilateral standoff, which had its own share of near-misses.

For all these reasons, nuclear deterrence should be seen as a time-buying strategy. It may provide us with the time it takes to overcome the political antagonisms that make nuclear deterrence necessary in the first place.

Paradoxical? Yes, but such is life.

N.B. The views expressed are the author’s own.