Abstract
Evidence suggests that a territorial dispute is almost a necessary condition for interstate war. By applying the diversionary theory of a relationship between domestic dissatisfaction and states' external aggression, the author examines the circumstances that push challenger states to use armed force in such disputes. This theory is refined by incorporating variables measuring risk and costs. The author contends that regime leaders are risk and cost averse, not risk and cost willing, as widely alleged. This applies in particular to democratically elected leaders. A new measure of dissatisfaction that draws on deprivation theory is provided. Using probit regression, an analysis covering 1950 to 1990 confirms most of the predictions but with two conspicuous exceptions: democracies are not more prone to use diversion than nondemocracies, and democracies show a disregard for the economic costs of armed diversion.