Deterrence theory: where do we stand?

Although deterrence theory was a central focus in the study of International Relations during the Cold War, attention has shifted away from deterrence since the end of that conflict. Nonetheless, deterrence is a general phenomenon that is not limited to any particular time or space. Moving beyond a simple focus on the US-Soviet relationship, scholars have recently begun further explorations of deterrence, through development of theory, analysis of policy alternatives, and empirical analysis. This article seeks to evaluate where deterrence theory stands today through: (1) a consideration of distinctions between different strands of theory; (2) a discussion of the assumption of rationality in deterrence theory; (3) an examination of three important distinctions in deterrence; (4) an evaluation of the difficult task of testing deterrence theory, and (5) an overview of recent theoretical developments. The primary conclusion is that perfect deterrence theory provides a logically consistent alternative to classical deterrence theory and therefore provides the most appropriate basis for further theoretical development, empirical testing, and application to policy.