The United States now incarcerates more people than any other country in the world, both as a percentage of its own population and in absolute numbers. The federal government operates a far-reaching network of immigrant detention centers and war prisons, including the notorious camp at Guantánamo Bay. Like the domestic warehouses of mass incarceration, these are spaces where the boundaries of legal personhood and cultural identity are contested. While prisons have been expanding, many other public institutions have disappeared or withered; those that remain, such as schools and housing projects, seem increasingly prison-like. Critics have described the United States as a “prison nation,” arguing that imprisonment, which serves various functions elsewhere, has become a core mission of the U.S. state, an end in itself (Herivel and Wright 2003). To claim that the United States, as a nation, is distinguished by its prisons is to pose a problem, not to resolve one, since prison stands for so many enduring contradictions—between assimilation and exclusion, deracination and racialization, subject formation and abjection.