This pioneering book, now thoroughly updated to incorporate important research, explains the causes of war through a sustained combination of theoretical insights and detailed case studies. Cashman and Robinson find that while all wars have multiple causes, certain factors typically combine in identifiable "dangerous patterns." Through their examination of World War I, World War II in the Pacific, the Six-Day War, the Indo-Pakistani War of 1971, the Iran-Iraq War, and the US invasion of Iraq, the authors lay out the complex multilevel processes by which disputes between countries erupt into bloody conflicts. Ideal for a range of courses in international relations at both the undergraduate and graduate levels, this focused text clearly explains theory and applies it to concrete case-study examples in a way that allows students to fully understand the origins of war.