Meet the author, Patrick Weil, and listen to a conversation about his new book. Present-day Americans feel secure in their citizenship: they are free to speak up for any cause, oppose their government, marry a person of any background, and live where they choose—at home or abroad. Denaturalization and denationalization are more often associated with twentieth-century authoritarian regimes. But there was a time when American-born and naturalized foreign-born individuals in the United States could be deprived of their citizenship and its associated rights. Patrick Weil examines the twentieth-century legal procedures, causes, and enforcement of denaturalization to illuminate an important but neglected dimension of Americans' understanding of sovereignty and federal authority: a citizen is defined, in part, by the parameters that could be used to revoke that same citizenship. Commentary by Linda Greenhouse.