Since the attacks of September 11, 2001, the United States government has pursued a series of energetic policies designed to protect America from the threat of Islamist terror networks. (1) Some of these policies are intensely controversial. (2) Critics in other countries protest that the United States has acted in defiance of international law. Some of this criticism has been embraced by domestic opponents of the Bush administration, particularly those in American law schools. Professor Jeremy Waldron, for example, offered a version of such criticism during the 2005 Federalist Society Student Symposium and in earlier writings, illustrating the larger pattern of criticism.
The purpose of this Article is not to mount a defense of any particular American policy of recent years. Instead, this Article challenges the critics' underlying premise that international law has the same sort of claim on our government as domestic law and that war measures abroad can accordingly be judged in the same terms as police abuses at home.
The arguments in this Article follow the three general kinds of arguments advanced by critics of international law. First, international law does not usually have the clarity and specificity of domestic law, particularly in most areas invoked by critics. International law in these areas is "law" by courtesy or aspiration more than it is a reliable guide to actual international conduct. Second, although some critics try to escape the obvious legal deficiencies of international law by appealing to the underlying values that treaties are supposed to embody, as soon as one looks behind limited or ambiguous treaties to seek out the fundamental principles of those treaties, one must quickly reckon with the most fundamental principle: the right and obligation of self-defense. As the Founders saw it, that principle was paramount to any legal standard. Will such arguments leave international law without any moral force? Should nations not, as some critics suggest, hearken to international standards to preserve at least the possibility of a lawbound world? The last section of this Article addresses this argument, with this countering point: If international standards are to reflect enduring principles of justice, they must be flexible enough to accommodate new circumstances. It is not in America's interest--in the longer view, it is in no one's clear interest--to try to preserve dysfunctional international standards merely for the sake of showing devotion to the idea of standards.
I. INTERNATIONAL LAW IS LESS RELIABLE THAN DOMESTIC LAW
The idea that some legal standards transcend national boundaries--that otherwise independent nations are subject to a more general law of right conduct--is an old idea. According to Hugo Grotius, the seventeenth-century Dutch jurist, this idea was already well recognized among the ancient Greeks and Romans. (3) But Grotius, like his predecessors, still associated this more general law with jus gentium ("law of nations"). (4) This older term was used by Roman jurists and was then adapted by medieval commentators who gave it a somewhat different significance. (5) The term implies something broad, encompassing, and perhaps foundational--a law recognized by all nations. Hence, as Grotius indicated, it was a law closely related to the law of nature. (6) Later in the seventeenth century, the German jurist Samuel Pufendorf, often regarded as an intellectual heir to Grotius, published a treatise called De Jure Naturae et Gentium ("On The Law of Nature and Nations") highlighting the close connection between the law of nature and law of nations. (7)
By contrast, the modern term "international law" sounds much more specialized and precise than the "law of nature." Legal studies are divided into subjects like "labor law," "tax law," and "contract law." International law is often referred to as if it were one more well-defined body of distinctive rules and procedures. …