This Vast Southern Empire by Matthew Karp

Slaveholders at the Helm of American Foreign Policy

In the antebellum decades, the planter elite drove American foreign policy to protect and extend slavery abroad, using diplomacy, war, and covert filibustering to seek new slave territories and markets; they cast expansion as essential to the nation’s security and prosperity, shaped debates over interventions like the Mexican-American War and efforts to acquire Cuba, and transformed national rhetoric to legitimize racial hierarchy, making the defense of slavery a central organizing principle of U.S. international affairs and a crucial driver of sectional conflict.

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