This book offers a new approach to global justice that integrates the work and insights of both disciplines. It offers an analysis of the international legal order through the lens of contemporary ethical theories. My specific thesis is two-fold: (1) the core components of the international legal system, even if they came about as a result of political compromises, power politics, and historical contingencies, largely already conform to an ethical vision of justice, one that I term a “thin” justice, that provides the key foundations for a just world order; and (2) the major shortcomings of the existing rules and institutions of that legal system, either in not meeting the thin standard or in their distance from a thicker standard, can best be appraised and improved with the aid of ethical theory.
The first goal, then, responds to ethical inquiries that have discounted or misunderstood much of the normative character of international law, and, it is hoped, will spur an interest on their part with an understanding of international law, a respect for its normative foundations, and the need to use international law to advance global justice. The second is a response to international legal scholarship that has failed to consider the role of ethical thinking in solving our most pressing problems. Lawyers who limit their inquiry to the internal coherence of the system but fear approaches outside the law to improve that system constrain their roles as contributors to an improved international legal order. Moral thinking should not be considered an embarrassing sideshow, but an essential project for an improved legal order. Indeed, my claim is that decisions about the content and direction of the core norms of international law are decisions about the moral content of the law, requiring overt consideration of ethical theory.
An ethical appraisal of international law is not merely a project for scholars, however. Because international law is central to constructing a more just world order, we need to give international actors — from presidents and prime ministers to ordinary citizens, from business tycoons to leaders of rebel movements — good reasons to respect it and develop it, or good reasons to change it or supplement it. When a set of norms is morally defensible under a considered moral viewpoint, we have provided those actors additional reasons for respecting it beyond just the fear of adverse consequences for ignoring the rules, and a good reason to appreciate the consequences of altering the law and its institutions in one direction or another. So my aim here is to provide those good reasons for stasis or change.