Jackson, though born in South Carolina and an advocate for states’ rights, took a hard line, getting authorization to use military force against the state to enforce the law, though a compromise tariff ended up resolving the crisis without armed conflict.

But assuming that this type of strong leadership, leavened with compromise, would have staved off the Civil War is dubious, for reasons raised by the rest of Trump’s answer: “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?”

In fact, of course, many, many people do ask that question. (One might imagine that Trump, as a creature of Twitter, might be aware of the endless debates about the war in that platform.) What’s more, it is a question that has been definitively answered. The Civil War was fought over slavery, and the insistence of Southern states that they be allowed to keep it. (You needn’t take my word for it: Read the statements of the states that seceded, and their leaders, making the case.)

It is difficult to imagine that Jackson, as a Southern slaveholder and defender of slavery, would have been willing to stand against the South in the event of a civil war. But that’s ultimately beside the point: Even if he had, such a position would likely have stood little chance of preventing the war, which flowed from the Southern commitment to slavery.

Trump’s assertion that Jackson could have staved war off is a manifestation of Trump’s central, and perhaps only truly committed, political beliefs: a faith in the power of strength, and a faith in the power of dealmaking. It is why the president rushed to congratulate Turkish President Recep Tayyip Erdogan on a referendum empowering him and sapping democracy; it is why he is so fond of Egyptian President Abdel Fattah el-Sisi; and it is why on Sunday he invited the vicious Philippine President Rodrigo Duterte to the White House. If only there had been an Andrew Jackson in the White House, rather than a James Buchanan, goes the thinking, the war could have been averted.

To credit that requires two assumptions. The first is that the Civil War was tragic, a view my colleague Ta-Nehisi Coates dismantled in 2011: “One group of Americans attempted to raise a country on property in Negroes. Another group of Americans, many of them Negroes themselves, stopped them. As surely as we lack the ability to see tragedy in violently throwing off the yoke of the English, I lack the ability to see tragedy in violently throwing off the yoke of slaveholders.”

The second, related assumption is that there might have been some compromise in the matter. But given the Confederate states’ commitment to slavery, there was not: Either the Union could have thrown up its hands, allowed secession, and allowed slavery to persist, or else a war was inevitable, no matter the dealmakers or strongmen involved.