Abstract

States often invoke international norms to justify their foreign policy-making. In the last twenty years, a large body of literature has shown that norms matter in international politics since they provide frameworks for legitimate international action. Nevertheless, it is often overlooked that the absence of a centralized authority capable of enforcing and providing unambiguous interpretations of norms leaves states, particularly great powers, free to decide whether to recognize or reject the legitimacy of norms. In specific instances of foreign policy-making, states take actions that cohere with norms, while at other times they contest them. Operating in a decentralized system, international norms crucially depend on state support for their legitimacy, prominence, and effectiveness. Variations in the way states respond to norms call for an investigation into the domestic conditions that lead states to recognize or reject their legitimacy. These conditions will be investigated by comparing the attitudes of the United States and the United Kingdom towards the norms of humanitarian intervention and international criminal responsibility and by studying how these norms influence their policy-making. During the 1999 NATO intervention against the Federal Republic of Yugoslavia, both countries invoked the norm of humanitarian intervention. In contrast, during the 1998 Rome Conference for the adoption of the Statute of the International Criminal Court, their behavior diverged with the UK endorsing the Court and the US rejecting it. The analysis aims to discover the domestic actors that are responsible for how international norms are interpreted at the state level and the mechanisms and transmitters through which norms come to be viewed by states as legitimate or illegitimate frameworks of behavior.