Self-Enforcing International Agreements and the Limits of Coercion

International law provides an ideal context for studying the effects of freedom from coercion on cooperative behavior. To be sure, almost all academic discussions on the subject begin by asking whether international law constitutes law. But the category of all international law is too big and heterogeneous to permit useful analysis. Whether to regard, say, the rules governing the conduct of war or international humanitarian law as law presents radically different issues than analyzing the legal character of the Treaty of Rome (the constitutive instrument of the European Community), or the Warsaw Convention (the instrument governing contracts for the carriage of goods in international air transit). Instead, we will focus on a subset of international law, namely enforcement mechanisms for treaties and other agreements among states and, in particular, agreements that involve the joint production of social welfare. By limiting our inquiry to welfare-enhancing international agreements, we necessarily exclude customary international law. The lack of any clear consensus as to what customary international law means or does, along with the spotty practice of courts regarding its invocation, discourages us from attempting to explore its functional effects. Moreover, to the extent customary international law has any coherence, it seems to comprise an amalgam of tort and property rules, and we intend to explore the contributions that contract theory specifically can make to our understanding of the field. Accordingly, we will consider only the enforcement of express instruments entered into by states