A protracted US war against terror must combine military force with the resources of the criminal-justice system. And this exercise must be multilateral in two complementary senses: Military campaigns and their aftermath require the assembly of coalitions, the cooperation of allies, and the use of international peacekeeping forces and relief efforts under the aegis of international agencies. Furthermore, a war against terror necessarily requires the cooperation of many nations in hunting down and bringing to justice individual suspects. Simply to try all suspected terrorists before U.S. military tribunals intended for emergency battlefield conditions would put America at odds not only with its own domestic constitutional safeguards but with international conventions on the treatment of prisoners of war.