“Insane Aliens” and the Contradictions of Empire: Eugenics, Expansionism, and Nativism in the Early 20th-Century United States

In the late-19th and early 20th centuries, the leading intellectual and political movements in the United States were seemingly at odds: as expansionists pushed for territorial acquisitions abroad, nativists enacted restrictive immigration policies at home. Restrictionist policies were rooted in eugenics fears about the hereditary inferiority of non-white peoples, while maritime expansionists sought to expand the nation’s commercial and military power. Drawing on medical literature, media reports, and government reports, this paper explores how nativists made significant political gains by successfully linking Mexicans and other immigrant groups to insanity, criminality, and degeneracy. I examine the contradictions of a nation expanding into Latin America and the Caribbean while simultaneously curbing non-Nordic immigration, exploring how scientific racism played a role in both of these seemingly incongruous impulses.