The Security Dilemma Revisited

Robert Jervis's article “Cooperation under the Security Dilemma” is among the most important works in international relations of the past few decades. In it, Jervis develops two essential arguments. First, he explains that the security dilemma is the key to understanding how in an anarchic international system states with fundamentally compatible goals still end up in competition and at war. The security dilemma exists when “many of the means by which a state tries1to increase its security decrease the security of others.” It provides the rational foundation for what Jervis termed the “spiral model,” which describes how the interaction between states that are seeking only security can fuel competition and strain political relations.2Second, Jervis explains that the magnitude and nature of the security dilemma depend on two variables: the offense-defense balance and offense-defense differentiation.3As a result, the security dilemma can vary across space and time. Although states exist in a condition of international anarchy that does not vary, there can be significant variation in the attractiveness of cooperative or competitive means, the prospects for achieving a high level of security, and the probability of war.