The ideal model of national security decision making, whereby the legislative branch authorizes action to protect national security and the executive branch takes it, has broken down due to the speed and unpredictability of foreign crises and the president's monopoly on foreign intelligence. In response, Congress has ceded the initiative to the president, and then utilized the power of the purse to ratify or restrict what the president has done. This power, by necessity and preference, has become the central congressional tool for participating in national security policy. Inevitably attacks on policy are transformed into attacks on the making and effects of appropriations. In National Security Law and the Power of the Purse, William C. Banks and Peter Raven-Hansen offer a compelling discussion of the constitutional and statutory questions raised by these attacks and in the process suggest answers to these recurring questions. They look at the early history of the power of the purse in national security affairs to illustrate that appropriations for national security have historically played a special substantive role in controlling executive uses of the war power. The authors use this history as a basis for exploring the mechanics and scope of the power of the purse in contemporary national security, presenting Vietnam War appropriations and the Boland Amendments as case studies. National Security Law and the Power of the Purse offers a sophisticated and provocative primer on the power of the purse in national security law. It is essential reading for scholars and students of law and government, public administration, and national security and foreign affairs.