Matthew Karp’s This Vast Southern Empire: Slaveholders at the Helm of American Foreign Policy demonstrates how, before the Civil War, Southern elites dominated the State Department, the War Department, the Navy Department, and the Foreign Service. Slaveholders held the position of secretary of state for two-thirds of the antebellum period, while the secretaries of war and of navy were Southerners for four-fifths of that time. In the years before the Civil War, W. E. B. Du Bois once calculated, 80 out of 134 American diplomats were from the slave states.
In an era when slavery was under attack and retreating abroad, the US emerged as the institution’s paladin. The great British historian and politician T. B. Macaulay lamented that the “United States’ Government has openly declared itself the patron, the champion, and the upholder of slavery … It renders itself illustrious as the evil genius of the African race.” As Karp correctly observes, “British emancipation [in 1833] would transform the way southern elites thought about foreign affairs more forcefully than any other global event between the American Revolution and the Civil War.” Our popular national narrative does not dwell on the fact that by the early 1840s the United States was willing to rattle sabers with Britain over Texas, where Mexico had abolished slavery and American immigrants had reinstituted it. Although many still have a romanticized view of the Alamo and of Texas’s fight for independence, the Mexican War was intended to secure the vast area for slavery.
The spread of antebellum America was not simply a westward expansion against Native Americans; it carried within it the possibility of perpetual slavery for the vast majority of the inhabitants of the American tropics. Some Southerners hoped their country would become the great axis of an alliance of bondage, helping to prop up the institution in Brazil and in the remaining Spanish empire. Some enthusiasts even hoped that one day Southerners would exploit black labor on the banks not only of the Mississippi but even of the Amazon. In the 1850s, schemes to annex Cuba and its enslaved laborers came and went. Indeed, as Karp points out, on the eve of the Civil War some compromisers in the North thought they might appease the South by giving it Cuba.
Over 150 years after the Civil War, we are still haunted by the specter of slavery.