Communists, aliens, terrorists: Lurking just out of sight—or perhaps, maddeningly, already inside us—a dangerous enemy is plotting our downfall. From Colonial era encounters with Native Americans, to the Salem witch trials, the specter of slavery (and a slave revolt), the Red scares of the 1920s and 1950s, to the terrorist threat of today, American national identity has often been defined in opposition to a perceived threat. Who are they ? What do they want, how do we recognize them, how do we stop them? And who, in this conflict, are we ? Reading texts from Cotton Mather, Frederick Douglass, Charlotte Perkins Gilman, Walt Whitman, and Gish Jen, among others, and viewing films and TV, for example, “Invasion of the Body Snatchers,” “The X-Files,” and “Homeland,” we analyze the national psyche as it confronts (or imagines) moral corruption, spiritual possession, political subversion, subliminal brainwashing, and physical abduction.