INTERNATIONAL LAW AND
The instrumental theory of international law outlined in parts 1 and 2 was offered as an alternative to the conventional wisdom that international law has a normative component that pulls states toward compliance, contrary to their interests. Some traditionalists will claim that our purely positive, or explanatory, analysis is not responsive. Even if international law is best explained by states acting in their selfinterest, states should obey international law’s moral command. On this view, our preoccupation with the conditions under which states in fact comply with international law is of little interest. The important issue is what states should do; international law scholarship should press states to live up their obligations, regardless of whether it is in their interest to do so.
This argument’s assumption, an assumption that permeates modern international law scholarship, is that states have a moral obligation to comply with international law. In this chapter, we argue that this assumption is wrong. Our claim is not that states should not follow international law, but that they have no moral obligation to do so. A state’s instrumental calculus will usually counsel in favor of international law compliance, at least with respect to treaties that the state entered into self-consciously. But when the instrumental calculus suggests a departure from international law, international law imposes no moral obligation that requires contrary action. (For a discussion of the literature, see Buchanan and Golove 2002.)