After drawing parallels between the methods of mapping and those of economic modeling, this article seeks to uncover the implicit world map in J. M. Keynes’s 1933 essay “National Self-Sufficiency.” A close reading of that essay demonstrates that Keynes’s articulation of the concept of the national economy rested on a specific political-economic geography, which often obscured a view of the global and indeed imperial distribution of power and resources. The article then suggests that those epistemological and spatial assumptions helped shape the conceptual infrastructure on which subsequent models of macroeconomic intervention grew after World War II.