In response to the terrorist attacks of September 11, 2001 the United States has taken exceptional national security measures, particularly with respect to noncitizens. Many of those measures either expressly or at least arguably entail “profiling” young male Arabs and Muslims. They are summarized in the first section of this Article. The next section offers an analytical framework for evaluating a profiling program from a policy standpoint; it maintains that no profiling practice is justified unless it satisfies certain minimum requirements of rationality and weighted cost effectiveness. The final section suggests that some of the national security-related profiling practices raise serious issues of U.S. compliance with its obligations under the Convention on the Elimination of All Forms of Racial Discrimination.