Paul R. Pillar
Deterrence, United States
During the Cold War, no concept was more central to U.S. national security strategy and to the relationship between the superpowers than deterrence. The concept long predates the Cold War, of course, but during that four-decade competition between the United States and USSR, strategists and scholars developed a detailed and still valid doctrine of deterrence. Nuclear weapons and a strategic arms race made that doctrine especially necessary and significant, but the complexities of deterrence extended to other levels of international conflict and competition, such as the confrontation in Europe between armies of NATO and the Warsaw Pact.
Deterrence is a very useful component of national security policy, in at least two respects. It is a way to avoid highly damaging outcomes without having to disarm or disable an adversary—which often would be exceedingly painful and costly to do. It is a way to protect interests that may be difficult or even impossible to defend, if an undeterred adversary ever were to attack those interests.
Deterrence can be useful to the United States even when it is not one of the parties to a deterrent relationship, and even when those being deterred include purported friends and allies of the United States as well as its adversaries. If mutual deterrence between local or regional rivals keeps a war from breaking out, so much the better for everyone, including the United States, having an interest in wars not breaking out. This may even save the United States from getting dragged directly into such a war. Mutual deterrence between regional rivals also can be an ingredient in preventing anyone from dominating an entire region.
Deterrence has a wide range of applicability, but that applicability, even on national security matters, too often goes unrecognized. Much discussion of international terrorism, for example, has contained the assumption that terrorists cannot be deterred. But more careful analysis of the motivations of terrorists reveals that deterrence can be an important element in counterterrorism.