The idea that international law and institutions represent cooperative means for resolving inter-state disputes is so common as to be almost taken for granted in International Relations scholarship. Global-governance scholars often use the terms international law and cooperation interchangeably and treat legalization as a subset of the broader category of inter-governmental cooperation. This paper highlights the methodological and substantive problems that follow from equating ‘global governance’ with ‘international cooperation’ and suggests an alternative. The traditional model applies liberal political theory to the study of international institutions and interprets global governance as the realization of shared interests. It deflects research away from questions about trade-offs and winners or losers. In place of cooperation theory, I outline an overtly political methodology that assumes that governance – global or otherwise – necessarily favors some interests over others. In scholarship, the difference is evident in research methods, normative interpretation, and policy recommendations, as research is reoriented toward understanding how international institutions redistribute inequalities of wealth and power.

Why has interstate war declined and why do states refrain from territorial conquests in the post-Second World War order? The 1928 Peace Pact cannot account for these remarkable developments. This article argues that outlawing war is not enough to promote international peace. International Relations debates on the influence of weapons of mass destruction, democratic regime types and political cultures on interstate behaviour provide further important insights into the delegitimation of certain types of war. Since the 1990s, a changing character of war and warfare has emerged that is especially promoted by democratic states. How democratic states have justified their military use of force and how they have conducted their military interventions has a strong and ambivalent impact on the liberal world order.