POWER DIFFERENTIALS AND WAR IN RIVAL DYADS

The relationship between static and dynamic power distributions and wa r is a central element in the realist literature of international poli tics. The distribution of power and shifts in these distributions are held to be a principal source of conflict in works from Thucydides to Waltz. Most attempts to test empirically for a structural association between capability distributions and conflict have treated disputes as independent events; however, over the last two centuries a disproport ionate amount of interstate conflict has occurred in the context of ex tended dyadic rivalries. This study focuses on the conflict patterns o f these ''enduring rivals.'' Based on a Markov chain analysis of 456 m ilitarized disputes occurring between 1816 and 1986, the findings indi cate that power parity and shifts toward parity are approximately twic e as likely to be associated with war as is a condition of power prepo nderance. By definition, rival dyads have issues in conflict. Equality of power or shifts toward equality create a situation in which both s ides can perceive the potential for successful use of force. The findi ngs generated in this analysis indicate that with such power distribut ions war between rival nations is most probable.