As the technology for regulating travel evolved from paper passports to massive computerized databases, the American bureaucratic system for regulating travel has grown from a small office in Washington D.C. to a highly sophisticated network spanning the globe. Anyone whose name appears on the U.S. Government’s “No Fly List” may find his or her air travel prohibited if anonymous analysts in a small FBI office secretly conclude that the person “may be a threat to civil aviation or national security.” I trace the history and scope of U.S. travel regulations, beginning with the story of Ruth B. Shipley, who almost single-handedly controlled access to passports during the Cold War, to the No Fly List. I argue that U.S. citizens’ freedom to leave their country and return is a fundamental right, protected by the Constitution. And I argue that all persons have certain procedural rights that the No Fly List infringes.