National security policy can resemble the fashion industry. A defense strategy that is in vogue in one era can fall out of fashion, only to come back into style, perhaps in slightly different form, at a later date. So it is with deterrence. This strategy was central during the Cold War, but 9/11 convinced many people that deterrence was no longer useful. In the years after, however, interest in deterrence revived as scholars and government officials sought ways to adapt it to meet contemporary threats.
This deterrence revival is a mixed blessing. Just as it was during the Cold War, deterrence remains both necessary and dangerous. As long as there are actors willing to contemplate the use of violence to achieve their ends, seeking ways to deter attacks will remain important. But relying on deterrence is risky, and a preoccupation with deterrence can lead to unwise decisions.
To get a better sense of whether deterrence can be of value in today’s security environment, it is worthwhile examining how it might apply to three “asymmetric” threats: terrorism, so-called rogue states armed with nuclear, biological or chemical (NBC) weapons, and cyberattacks. Despite claims to the contrary, deterrence is still relevant and can make useful contributions to security, but policymakers also need to understand its limitations. As a familiar concept that promises to provide security without the need to go war, the idea of deterrence can be quite seductive. This makes it important not to become obsessed with deterrence or ask more from it than it can deliver.