Contemporary attention to presidential war power focuses on the possibility of ”perpetual war.” This essay contextualizes that controversy by returning to the nation’s first international crisis - the War of 1812 - to consider the ways James Madison’s rhetoric established precedents that empowered presidents to act with rhetorical impunity in international affairs. Analyzing an overlooked but influential anti-war pamphlet written by John Lowell reveals public concerns about Madison’s War and the dangers presidential rhetoric poses to the constitutional order. In doing so, this essay revises contemporary thinking about the imperial presidency, the rhetorical presidency, and the nature of perpetual war.