In 2003, American policymakers linked the democratization of Iraq with greater peace, democracy, and prosperity in the Middle East. We elaborate this regional-level policy argument theoretically and test it empirically on a global sample of states for the twentieth century. We differentiate the impact of fully and weakly democratic externally imposed polities (“bright” versus “dim” beacons, respectively) on regional interstate war, democratization, and economic growth. We conclude that (1) bright beacons reduce, while dim beacons increase war; (2) bright beacons do not stimulate democratization, while dim beacons undermine democratization; and (3) bright beacons stimulate prosperity, while dim beacons undermine prosperity.