The causes of war and the conditions of peace

I organize this review and assessment of the literature on the causes of war around a levels-of-analysis framework and focus primarily on balance of power theories, power transition theories, the relationship between economic interdependence and war, diversionary theories of conflict, domestic coalitional theories, and the nature of decision-making under risk and uncertainty. I analyze several trends in the study of war that cut across different theoretical perspectives. Although the field is characterized by enormous diversity and few lawlike propositions, it has made significant progress in the past decade or two: Its theories are more rigorously formulated and more attentive to the causal mechanisms that drive behavior, its research designs are more carefully constructed to match the tested theories, and its scholars are more methodologically self-conscious in the use of both quantitative and qualitative methods.