Does Conquest Pay? demonstrates that expansion can, in fact, provide rewards to aggressor nations. Peter Liberman argues that invaders can exploit industrial societies for short periods of time and can maintain control and economic performance over the long term. This is because modern societies are uniquely vulnerable to coercion and repression. Hence, by wielding a gun in one hand and offering food with the other, determined conquerors can compel collaboration and suppress resistance.

Liberman's argument is supported by several historical case studies: Germany's capture of Belgium and Luxembourg during World War I and of nearly all of Europe during World War II; France's seizure of the Ruhr in 1923-24; the Japanese Empire during 1910-45; and Soviet hegemony over Eastern Europe in 1945-89.

Does Conquest Pay? suggests that the international systems is more war-prone than many optimists claim. Liberman's findings also contribute to debates about the stability of empires and other authoritarian regimes, the effectiveness of national resistance strategies, and the sources of rebellious collective action.