For centuries, international law regulated relations between states. With rare exception, it did not create rights for individuals, nor impose responsibilities on individuals. That has changed dramatically in the last few decades. The adoption of the Genocide Convention in 1948, the Geneva Conventions in 1949, several human rights conventions in the 1960s, such as the Covenant on Civil and Political Rights, and treaties focusing on specific aspects of terrorism, from airplane hijacking to transportation of nuclear material, have resulted in the creation of a significant body of substantive international law giving individuals rights—even against their own government—and holding individuals responsible for their acts....