Geopolitics has become marginalized in modern international relations scholarship despite its foundational role. This essay seeks to bring geopolitics back to the mainstream of international relations through conceptual, historical, and theoretical analyses. I make three arguments. First, definitional confusion about geopolitics comes from an overly broad understanding of geography. Notwithstanding various uses, however, geography itself should be re-centered as the analytical core of geopolitics. Second, classical geopolitics sought to inform grand strategy using geography as an explanatory variable and was thus institutionalized in U.S. strategic education. To wit, geography was used as “an aid to statecraft.” Finally,...