Matthew Karp, This Vast Southern Empire: Slaveholders at the Helm of American Foreign Policy (Cambridge: Harvard University Press, 2016).

For decades, historians portrayed American slavery as a backward institution destined to wither in the onrushing tide of modernity. In the 1970s, Eugene Genovese’s Roll Jordan Roll conjured images of a lost feudal world of master and slave. In the 1930s, even Du Bois’s Black Reconstruction argued that slavery “would have disintegrated of its own weight” had the Civil War not intervened. Whatever it was, American slavery was not modern, progressive, or efficient.

Based on anecdotal conversation with those who are not historians, my guess is that this is still the popular consensus. But in recent years historians have challenged this view. In the work of Walter Johnson, Edward Baptist, and Sven Beckert, we see a system of slavery that is adaptable, modern, capitalistic, and forward-looking. This Vast Southern Empire bears the imprint of the new scholarship on American slavery, but it’s really a book about foreign policy.

It has often been pointed out that the South dominated the federal government until 1860. Usually, a slaveowner sat in the White House, and the South enjoyed disproportionate power in congress and the judiciary. But what exactly did white southerners do with that power? In Karp’s narrative, it’s not just that southern elites sought to maintain a stranglehold on the federal government in a sectional battle for supremacy between North and South. They had bigger ambitions. From the broader perspective of foreign relations, the entire American state was a vehicle for the promotion of slavery. Southern slaveholders were not narrow sectionalists, but nationalists who skilfully used the federal government to promote a foreign policy of slavery.

The same southerners who feared federal power at home counted on its vigorous application abroad to advance a “hemispheric defense of slavery.” It was no coincidence that southerners led the effort to modernize and enlarge the army and navy in the 1840s and 1850s. Southerners annexed Texas, spurred the invasion of Mexico, and engaged in diplomatic intrigues in Europe and South America to thwart British abolitionist aims. Their vehicle for these endeavors was, simply, the American state.

Karp convincingly shows that the filibuster invasions of Nicaraugua and Cuba in the 1840s and 1850s are the wrong place to look for the global ambitions of southern slaveholders. Why turn to private armies and hapless adventurers when the vast powers of the federal government lay at their disposal?

Karp shows that southern elites were not reflexive supporters of expansionist schemes. Theirs was a foreign policy that regarded sovereignty as less important than social organization. Cuba would make a nice addition to the American union, but a slave-based Cuba under Spanish rule was better than an American-ruled emancipated Cuba. Southern slaveholders regarded monarchist Brazil and Spanish Cuba as allies and parliamentary Britain as a dangerous foe. Differences in governance aside, Brazil, Cuba, and the United States shared a common interest in protecting racial slavery from the influence of British abolitionism after 1833.

In this light, the crisis of 1860 looks different. Karp writes that Lincoln’s election was a revolution not just in the domestic balance of power between North and South, but in global power relations. For over two decades, the United States had acted as the pro-slavery counterweight in the western hemisphere to abolitionist Britain. With Lincoln’s election, the world’s leading promoter of slavery had effectively–and suddenly–switched sides.

Southern elites’ headlong rush into self-destruction in the crisis of 1860-1861 has long been a cause of fascination and debate. What was the source of their hubris? Karp demonstrates that slaveholders’ confidence was not only based on the narrow calculation that British mills could not forgo southern cotton. More broadly, many southern elites looked around the globe and persuaded themselves that the world was trending in their direction.

The most respected scientists on both sides of the Atlantic seemed to have established beyond reasonable doubt the fact of white racial supremacy, and the influence of scientific racism was growing by the day. Economically and geopolitically, too, southern slaveholders had reasons for optimism. Britain had passed its emancipation bill in 1833, and then watched as the economic value of its Caribbean colonies promptly collapsed. Britain’s subsequent resort to various forms of coerced labor was seen among southern elites as a kind of vindication. Europe’s imperial powers might have been opposed to slavery, but they were self-consciously white supremacist empires using the labor of people of color and violently extending their rule over new territories. They were, in other words, groping toward the economic and scientific “truths” the slaveholding South had already discovered.

Good historical scholarship allows us to see the past in new ways and imagine what might have been. After reading This Vast Southern Empire, it is easier to see why southern slaveholders believed they were on the right side of history, and it is almost surprising that their bold and despicable plans failed.