Authors of books about just war theory have two motives: one is theoretical; the other is practical. Theoretically, we are vitally interested in answering the question: What is just war? What aims and practices of war are morally permissible? In doing so, we hope to be eminently practical as well and swell with pride when we hear statesmen proclaim, as did President Obama in 2009, that “the problems of war ... require us to think in new ways about the notions of just war and the imperatives of a just peace.” His remarks link the successful prosecution of war with its just conduct. Most just war theorists hope this is true.

Scholars of civil wars, less prone to wax moralistic, are also engaged by the theoretical and practical questions of war. Theoretically, they seek to understand the causes of civil war and the violent enmity it releases while grappling with those factors that perpetuate war or bring it to an end. Practically, they, too, hope to offer statesmen and policy makers the tools to prosecute wars successfully, conduct effective counterinsurgencies, and realize an enduring peace.