On Sunday, President Donald Trump talked about his first one hundred days in office with Salena Zito, a writer for the Washington Examiner. Commenting on his recent visit to Tennessee, Trump had this to say about one of his predecessors in the White House:

I mean, had Andrew Jackson been a little later, you wouldn’t have had the Civil War. He was a very tough person, but he had a big heart. He was really angry that he saw what was happening with regard to the Civil War. He said, ‘There’s no reason for this.’ People don’t realize, you know, the Civil War -- if you think about it, why? People don’t ask that question, but why was there a Civil War? Why could that one not have been worked out?

Oh, the howls that erupted from the commentariat at Trump’s supposed ignorance of American history. “Big heart”??? Jackson was a slaveowner! Jackson slaughtered Indians! Jackson’s signing of the Indian Removal Act in 1830 started the Cherokee on the Trail of Tears, during which 4,000 Cherokee died.

John Nichols wrote in the Nation that “The theory that ‘had Andrew Jackson been a little later, you wouldn’t have had the Civil War’ is just wrong. Jackson’s presidency finished almost a quarter century before the Civil War began. Jackson died 16 years before the war began.”

Yes, Mr. Nichols, we know that. The president was playing the popular game of “What if?” We’ve all played it. “What if Oswald had missed?” “What if Hitler had been assassinated in the 1920s?” “What if the D-Day invasion of Normandy had failed?” -- and what if Andrew Jackson had been President when the Civil War began?

Trump wondered why no one asks why the Civil War could not have been avoided. In reality, the question is asked all the time. But there’s nothing ridiculous about the question itself. The countries of Latin America -- and England -- abolished slavery without civil war, most of them earlier than the United States.

Liberals, however, reacted as though Trump was making an apologia for slavery. Liberals thought that Trump was sending a coded message of support to the white nationalists and white supremacists of the alt-right. That is a laughable conclusion and it is not what Trump was saying.

A Facebook comment mocked Trump’s apparent belief that one man could have derailed the historical forces that brought about the Civil War. Did the commenter know that he was attacking the “Great Man” theory of history? This was the view, popular in the 19th century, that “Great Men” (Napoleon, Bismarck, etc.) make history.

The Great Man theory of history has long been discredited. Still, does anyone believe that it makes no difference who occupies the presidential chair during a crisis? The first of the Southern states to secede was South Carolina on December 20, 1860. Lincoln had been elected the month before, but the ineffectual James Buchanan was still president. Buchanan comes dead last in historians’ rankings of presidents. Historian Robert Strauss’ 2016 book on Buchanan is titled Worst. President. Ever.

Consider Buchanan’s response to the dress rehearsal for the Civil War dubbed “Bleeding Kansas” by New York Tribune editor Horace Greeley. From 1856 to 1859, Kansas, not yet a state, was torn between anti-slavery “Free-Staters” and pro-slavery “Border Ruffians.” Rival bands of armed men roamed Kansas killing. President Buchanan did nothing to stop the violence.

Buchanan also did nothing when South Carolina seceded. Buchanan believed that secession was illegal, but that the U.S. Constitution gave the federal government no authority to stop it.

Suppose someone other than Buchanan had been president when South Carolina seceded? Someone who did not hold Buchanan’s futilitarian beliefs. Someone like -- oh, I don’t know -- Andrew Jackson.

A president in Jackson’s mold could have prevented the Civil War. Jackson provided the blueprint in his successful handling of the Nullification Crisis of 1832-1833.

The Nullification Crisis arose over an issue which divided North and South almost as bitterly as slavery: tariffs. The North relied on a high tariff to provide revenue and to protect its manufacturers. The South, with little manufacturing, opposed tariffs. The clash between the sections over the tariff came to a head with the passage of steep tariffs in 1828 (the so-called “Tariff of Abominations”) and 1832.

Jackson’s own vice president, John C. Calhoun, had given Southerners the means to fight back. Calhoun was the anonymous author of the "South Carolina Exposition and Protest" which argued that any state could “nullify” a law the state deemed unconstitutional. On November 24, 1832, South Carolina passed an “Ordinance of Nullification” declaring the 1828 and 1832 tariffs null and void within its borders. South Carolina then refused to collect federal import tariffs.

Jackson, like Abraham Lincoln after him, believed passionately in Union. Jackson demonstrated his devotion to Union at a Jefferson Day dinner also attended by Calhoun. Calhoun proposed the toast: “The Union -- next to our liberty, the most dear!” This was in response to Jackson’s toast: “Our federal union -- it must be preserved!”

President Jackson’s response to South Carolina’s Ordinance of Nullification was twofold. Jackson was open to compromise and worked to bring down the tariff. But Jackson also made clear that if necessary he would use force. On March 2, 1833, Congress enacted a “Force Bill” granting Jackson the discretion to use troops against South Carolina. This proved to be unnecessary. Congress’ enactment of a compromise bill lowering tariffs over the next ten years persuaded South Carolina to abandon nullification.

Had Jackson been president in 1860 he would have crushed South Carolina’s latest rebellion with the same firmness. Using a small amount of force early on when just one state had seceded could have prevented the massive bloodletting of the Civil War which killed 800,000 Americans on both sides.

Yes, Jackson owned slaves. Yes, Jackson believed that blacks and Indians were inferior to whites. There’s no excuse for that. But Jackson sided against his fellow southerners during the Nullification crisis. The Civil War might have begun twenty-eight years early, in 1832, had it not been for Jackson.

Trump understands history better than we give him credit for.