A unified model of war onset and outcome

Recent work regarding what influences the chances that states either win or lose wars focuses on two primary explanations. The first suggests that states win or lose largely on the merits of their war-fighting strategies and capabilities. The second explanation asserts that successful states simply choose their fights more carefully, thus selecting opponents they are more likely to defeat. Although these approaches are often perceived as contending theories, they actually are complementary in that both contribute to a unified explanation of why states win wars. This article provides a theoretical explanation of success in war by joining these two approaches and arguing that because the explanations are complementary, analyses ignoring one or the other are incomplete. We report a series of censored probit models that unify these explanations. The results of the unified model support the argument that the theories should be considered complementary. Our conclusions point to the importance of conceiving of international phenomena including conflict as processes rather than as discrete events.