Abstract
How should international law figure into the practical reasoning of agents who fall under its jurisdiction? How should the existence of an international legal norm regulating some activity affect a subject’s decision-making about that activity? This is a question concerning the general moral authority of international law. It concerns not simply the kind of authority international law claims, but the character of the authority it actually has. An authority, as I will use the term, is moral obligation producing: if x (e.g., a person, institution, or law) has authority over an agent, then the directives of x produce a significant reason for the agent to comply with the terms of the directive. This paper concerns the sense in which international law, and the law of nascent legal systems generally, generate moral obligations for their subjects, i.e., for those who fall under their claimed jurisdiction.