“People don’t ask that question, but why was there a Civil War?” President Donald Trump famously mused aloud during an interview on Sirius XM radio on May 1. “Why could that one not have been worked out?”

Why indeed? Twitter and cable news instantly rang with a chorus of voices ranging from Chelsea Clinton to Lindsey Graham, noting that almost everyone who has thought about American history for 20 minutes has considered the question Trump posed — and that the answer was simple: slavery. Many pointed out that a version of Trump’s question about the origins of the Civil War even appears on the US citizenship test — which covers only the basics.

Trump’s larger point, however — if we give him the benefit of the doubt and assume coherence — is that despite the debates over slavery, war could have been avoided if the nation’s leaders had been “tough” enough. If Andrew Jackson had been alive, Trump argued, projecting his own image of himself as a great dealmaker, the slavery controversy could have been “worked out.”

In his bumbling, inarticulate way, Trump had hit upon an important question. In the long historiography about the Civil War, many historians have made the case that the war could have been avoided. Some of them even make that argument today: They are sometimes called “neorevisionists” or the “new revisionists.”

The first generation of “revisionist" Civil War historians, who worked from around 1918 to 1945 — so called because they sought to revise the sentimental consensus that 1) the war was unavoidable, and 2) it made the nation stronger and more united — tended to soft-pedal slavery and blamed the war on extremists in the North and South, the abolitionists and the “fire eaters.” Decades later, the neorevisionists take a very different route to the conclusion that the war need not have occurred: They focus on the centrality of slavery to the economy of the entire United States. These historians imagine — hardly with pleasure — a compromise that might have extended slavery for years longer.

Never mind what Andrew Jackson might have done in Trump’s alternate universe. Let’s focus instead on this question: Why couldn’t white Northerners and Southerners have worked out their differences without going to war? Though virtually all historians agree slavery was the cause of the conflict, they don’t agree on why slavery caused the war when it did. After all, the republic had held together for more than seven decades half slave and half free. In 1820, when the admission of Missouri as a slave state threatened to break the balance between free and slave states in the Senate, Congress agreed to simultaneously admit Maine as a free state and to prohibit slavery in any future states north of the 36°30′ parallel.

Congress struck a similar deal after the conquest of Western territories from Mexico: Texas and California were admitted as slave and free states, respectively; the slave trade was abolished in the District of Columbia; and citizens in free states were required to help return runaway slaves to their owners. Why couldn't white Northerners and Southerners have reached a compromise in 1860, as they had in 1850 and 1820? And if the United States had avoided civil war, what would that have meant for the millions of Americans living in bondage?

Reactions to Trump’s comments reflected the belief that compromise was impossible. Yet, over time, several schools of historians have challenged that view.

Historians don’t like to call anything inevitable, but reading the many reactions to Trump’s comments may give the impression that the outbreak of war in 1861 was precisely that. Yoni Appelbaum wrote at the Atlantic that “some issues ... aren’t amenable to compromise” and “some conflicts ... a leader cannot suppress.” Eric Foner, professor emeritus of history at Columbia University and the dean of Reconstruction studies, told Vice that the antebellum United States was made of two different “societies based on different systems of labor,” and that by 1860 this schizophrenia was no longer sustainable.

Yet for the (first) revisionist school of Civil War historians, whose ranks included James G. Randall of the University of Illinois and Avery Craven of the University of Chicago, it was far from clear that the war was inevitable. Instead, they accused abolitionists and fire eaters of overreacting when compromise remained possible. They believed slavery was an obsolete labor system and would have died out on its own without anyone having to fire a weapon.

They also believed that if cooler heads had prevailed, it would have been clear that Lincoln and the Republican Party had no intention of abolishing slavery where it already existed. Lincoln only wished to prevent the spread of slavery into the Western territories, which most historians believed were ill-suited for slave labor anyway. Lincoln's election, therefore, need not have led to secession and civil war.

The revisionists worked in the shadow of World War I, which had left many Americans cynical about war. They doubted whether any war could be fought for such noble purposes as to preserve the United States and free the slaves. When historians wrote that a “blundering generation” of leaders suffering from “war psychosis” marched unnecessarily to war, they could just as easily have been writing about Europe’s leaders in the fall of 1914.

But the revisionists also worked in the shadow of white supremacy. Though they blamed both the abolitionists and Southern die-hards for the war, they especially blamed the abolitionists, claiming they were overzealous and self-righteous in their attacks on Southern slaveholders.

Frank L. Owsley of Vanderbilt even argued — in 1940 — that the abolitionists “were threatening the existence of the South as seriously as the Nazis threaten the existence of England.” Craven reasoned that slavery was worse for the slaveholder than for the slave, since the latter didn’t have to worry about crop failures or debt. On the practice of slave breeding, Craven wrote sarcastically that since the slave could not select his own “life partner,” he suffered “a plight … as bad as that of European royalty.” It was no surprise the revisionists regarded the antebellum debates over slavery as molehills rather than mountains — and amenable to compromise.

That interpretation of the war has long been out of favor in universities, though it clings to life among neo-Confederates and racists. Indeed, one hears a suspicion among some historians today that Trump’s speculation — “Why could that one not have been worked out?” — is the first step on a slippery slope to slavery apologetics.

The journalist and Andrew Jackson biographer Jon Meacham pointed out “that any accommodation with the South would have to have ratified the continued existence of slavery in the old slaveholding states.” To wish the war had been avoided, in other words, is a close cousin to wishing 4 million African Americans had remained enslaved.

After World War II, the revisionist school gave way to a clash-of-civilizations interpretation that saw armed conflict as unavoidable

The revisionist school was superseded by what Gary Kornblith, professor emeritus at Oberlin College, has called the “fundamentalist” interpretation of the Civil War. Not to be confused with Jerry Falwell and his ilk, Civil War fundamentalists argued that because of slavery, the North and South were so different by 1860 — economically, socially, and politically — that secession and war were practically inevitable. This interpretation remains very influential, its bible being Battle Cry of Freedom, James McPherson’s entry in the Oxford History of the United States.

Like revisionism, fundamentalism is a product of its time. The civil rights movement gave white historians a newfound sympathy for abolitionists and their antislavery allies. Moreover, World War II made historians friendlier to the idea of the Civil War as a “good war.” Arthur Schlesinger Jr. likened the Northern struggle against the Southern slave power to America’s struggles against fascism and communism, and he argued war was sometimes the only way to defeat evil.

The fundamentalist position was also influenced by postwar “modernization” theory, the notion that all civilizations follow roughly the same path to modernity. (Think of the upward trajectory implied by the terms developing country and developed country.) American intellectuals were embarrassed by the apparently backward state of the South, so they argued the region was just a little behind on the path to modernity — a sort of Third World colony enclosed within the United States. While the Soviet Union pointed to Jim Crow as an indictment of American hypocrisy and injustice, American intellectuals distanced the South from the rest of the nation and thereby absolved America of the South’s sins.

A similar process occurred in Civil War historiography. The eccentric historian Eugene Genovese convinced many of his peers that slavery had made the antebellum South a quasi-feudalist, pre-capitalist society, ultimately irreconcilable with the capitalist, industrializing North. This interpretation of the antebellum North and South fit well within postwar modernization theory.

Moreover, if the North and South were fundamentally irreconcilable, that meant slavery was incompatible with American democracy. Slavery was not part of the body of America but rather some crudely transplanted organ the body was bound to reject. Americans could take pride in the defeat of slavery — and, by extension, Jim Crow — and not feel complicit in those same evils.

The rise of “neorevisionist” interpretations

Today’s new revisionists reject the fundamentalist interpretation. They do not believe the North and South were fundamentally different, and they manage to cast into doubt the Civil War’s inevitability without downplaying the horrors of slavery.

Though they don’t share the old revisionists’ belief that the Civil War should have been avoided, the new revisionists agree that the war could have been avoided. A number of things had to happen in order for the decades-long tension between slavery and freedom to become unmanageable. And these were things that did not have to happen, the neorevisionsts point out.

For example, in 1850 the nation’s two major political parties, the Whigs and the Democrats, had both Southern and Northern members. But for many different reasons — in part because the Democrats had co-opted their positions on tariffs and infrastructure spending — the Whig Party fell apart over the next decade, and an antislavery party with virtually no Southern members took its place: the Republicans. If, however, the Whig Party had lived, the partisan ties between Southern and Northern Whigs (and between Southern and Northern Democrats) might have prevented the slavery controversy from overtaking Congress.

Gary Kornblith went deeper into the counterfactual weeds in a 2003 article in the Journal of American History. He looked at the 1844 presidential election, where James K. Polk, a proslavery Democrat, narrowly defeated Henry Clay, a moderate antislavery Whig. If a few thousand voters in New York had voted for Clay instead of the third-party abolitionist James G. Birney, Clay and not Polk would have become president.

Clay, so far as we can infer from his campaign rhetoric and opposition to the US–Mexican War in our timeline, would likely not have invaded Mexico in Kornblith’s alternate timeline. If the United States had not invaded Mexico, we would not have conquered the territory that is now the American Southwest — and the debate over the westward expansion of slavery would have been less vitriolic. Less territory for slavery to expand to! Furthermore, a successful Clay presidency would have made for a stronger Whig Party, and in 1860 the partisan divide might have had more to do with banking and tariffs and less to do with slavery.

Some historians see slavery as more entwined with the Northern economy than previously believed — further complicating the story of the war

Other historians, though they don’t necessarily call themselves neorevisionists, undermine the fundamentalist notion that the North and the South were different societies. They maintain, for one thing, that the antebellum South was thoroughly capitalist and exceedingly profitable, resurrecting controversial arguments made by the economic historians Robert Fogel and Stanley Engerman.

Edward Baptist’s The Half Has Never Been Told shows how slaveholders drove their enslaved laborers beyond their breaking points — not because they were wedded to a feudal economic system, but to maximize profits and satisfy the increasing worldwide demand for cotton caused by the industrial revolution. Indeed, Baptist considers the slaveholders’ use of cotton-picking quotas and calibrated torture a technology of efficiency management akin to the assembly line and interchangeable parts.

Though not all historians agree slavery was capitalist per se, they agree slavery generated a great deal of wealth. In addition to selling the products of their slaves' labor, slaveholders obtained loans using their human property as collateral, which in turn allowed them to accumulate even more capital. And if slaveholders made money through slave-backed mortgages, their lenders made even more money.

The cotton picked by enslaved people made not only New Orleans but also New York rich. The farmer in Ohio grew wheat to feed the cotton planter in Mississippi and the textile worker in Massachusetts, who produced the cloth worn by the enslaved woman in Kentucky. The enslaved human body was, in short, an engine of wealth. If the steam engine and the railroad are symbols of American industrialization, then so is the lash.

Far from being in fundamental opposition, then, the North and the South yielded immense profits from their economic relationship. The old revisionists made a similar argument, but they did so to show how irrational the abolitionists and fire eaters were. These newer historians are instead saying: Slavery wasn’t a bug of the American system, but a feature. It was not some pig’s kidney transplanted into the American experiment. It was an intrinsic part of the body.

If the Civil War could have been prevented, that familiar question lingers: What would have happened to the “peculiar institution” of slavery? Here the new revisionists diverge greatly from the old. They don’t suggest that slavery was an archaic system on its way out. They suggest that it too, like other systems of production of the time, was ripe for modernization and adaptation. Enslaved people did not only labor in the cotton fields of Natchez, this school of historians points out — they also labored in the ironworks of Richmond and at the ports of Baltimore and Galveston.

There’s no reason, they propose, to think slave labor couldn’t have coexisted with the industrialization of the late 19th century, no reason to think enslaved people couldn’t have forged Alabama’s steel and laid Tennessee’s railroad tracks — that they couldn’t have drilled oil in West Texas or picked fruit in the San Joaquin Valley. Few historians are willing to go too far down the counterfactual rabbit hole, but suffice it to say there was plenty of economic incentive to retain a large enslaved labor force.

Perhaps by 1860, the debate over slavery had reached such a fever pitch, thanks in large part to the work of black and white activists in the North, that the status quo could not be maintained. But make no mistake: There were many men in 1860 who thought themselves great dealmakers, and given the right circumstances they may well have won the day.

Whatever deal could have been reached to avert the Civil War, it would have at the very least protected slavery where it already existed — and quite possibly have left the door cracked open for its expansion. The United States had prospered for decades "half slave and half free," and despite Abraham Lincoln's prognostication to the contrary, it may have continued to prosper with that paradox at its heart.

President Trump deserves much of the ridicule he got, but it is not self-evident that the United States had to fall into war in the 1860s. Today, however, when historians wonder why a compromise wasn't reached, they aren’t blaming extremists in the North and South. They are, rather, casting an unflinching eye on the intersection of racism and capitalism across all of the United States in the 19th century. They’re challenging the certitude of a generation of historians who preceded them. And they’re asking questions that don’t flatter the self-image of either the North or the South.

William Black is a PhD candidate in history at Rice University. Find him on Twitter @williamrblack.

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