This research focuses on a topic of central importance in the field of international relations: the initiation and escalation of international conflicts. The research assesses how domestic economic and political conditions, as well as international political and military ones, influence the decisions of policy makers to threaten and use military force. Two phases in the process of escalation of force are analyzed: 1) the initial decision whether to confront an adversary directly and threaten him with force, and 2) after such a challenge, the decision whether to escalate the conflict and engage in sustained and large-scale use of military force. A theoretical model is developed for both phases and tested by means of statistical analysis 1) on a sample of 13 enduring international rivalries in which threats to use force were plausible, or did in fact occur, and 2) on the total set of 90 cases of international deterrence crises between 1870 and 1985. A subset of cases, comprising some well-explained by the statistical analysis and some poorly explained, are examined in depth to assess the adequacy and limits of the statistical analysis. This research should help answer several kinds of questions important to the social-scientific understanding of international relations such as: are the influences on decisions to initiate a conflict or crisis also central to explaining decisions to escalate international crises, or are the causes significantly different; how important are domestic economic and political conditions in explaining international conflict behavior. Is a more aggressive and conflictual foreign policy often a response to internal problems and weaknesses; what is the relative importance of defensive vs. opportunistic and expansionary incentives in decisions to threaten and/or resort to the use of military force; how important is a reputation for firmness or conciliation in a previous crisis to the success of deterrence in a new crisis. The research promises to significantly enhance our understanding of these topics.
