Whenever President Trump talks about American history, it sounds like he's telling a joke. "Andrew Jackson, Fred Douglass, and Honest Abe walk into a bar ..." The punch line is he's not joking.
Does it matter? Granted, he may not realize that Frederick Douglass is retired and then some; he seems to have discovered only in 2016 that Lincoln belonged to the party of Lincoln; and he attributes his own ignorance to everyone else ("People don't ask the question, why was there the Civil War?"). Still, plenty of other issues demand our attention. Newt Gingrich dismisses the criticism, telling the New York Times, "There's a certain amount of hunting for 'what is it that Trump has done that's dumb?'" Fair enough. Barack Obama and George W. Bush both mangled the past on occasion. "Trump is learning history as he governs," Gingrich added — on the job, like a kid on the soft-serve machine at a Dairy Queen.
One obvious problem with Gingrich's defense is that a president does not perform merely mechanical tasks. We entrust that person with the making of history — a job that requires a grasp of both historical content and the historical method. The president and historian alike live in a world of everything. Nothing lies beyond consideration. Every event, every matter of concern, swirls and bobs in a sea of trends, traditions, accidents, choices, costs, attitudes and beliefs. The ability to understand connections, interactions and unintended consequences is crucial.
Take conflicts of interest. In refusing to produce his tax returns, Trump cites his election — as if the majority that voted against him doesn't matter. He's not only breaking with the relatively recent tradition of such releases but with a belief dating all the way back to George Washington that the presidency is an office of special weight, responsible to all Americans.
Then there's the Constitution's emoluments clause. It's one sign of how the Founders mortared a dread of corruption into the foundation of the republic. They believed in disinterested officeholders who would lack a stake in the scrum of the marketplace. That idea remains in our political DNA. Violating it weakens the president, perhaps fatally.
Historical knowledge and thinking foster respect for opposing views and the complexity of important issues. Our political DNA also contains a distrust of corporations, for example, but in rather contradictory strands, generating government regulation as well as anti-government populism.
Early American corporations were vehicles for directing private investment into public projects. States chartered them one by one for specific purposes, granting protections ranging from limited liability to monopolies. Trump's hero, Andrew Jackson, condemned corporations as bastions of "exclusive privileges" for the wealthy. He and his followers demanded free competition between natural persons. In an era before big business, radical populists embraced laissez-faire.
The rise of giant companies changed the terms of debate from privilege to power. "Already our great corporations are fast emancipating themselves from the State," Charles Francis Adams Jr. warned in 1869. The new populists wanted regulation. "We hold," a group of Grangers declared in 1873, "that a State cannot create a corporation that it cannot thereafter control."
When struggling with the fraught issues of economic growth, liberty, inequality and oversight, a president can benefit from a grasp of this historical continuum, a legacy of both the right and the left.
Critics have thoroughly savaged Trump's appalling suggestion that the Civil War could have been avoided. But let's think through his hypothesis. No Civil War would mean no emancipation and no Reconstruction. That means no 14th Amendment, which establishes a race-neutral definition of citizenship and holds the states to the Bill of Rights. Before Reconstruction, states often violated civil liberties, banning abolitionist speech and imposing religious tests on voters.
In other words, African Americans did not merely win freedom and existing rights. Rather, the era redefined our concepts of citizenship and liberty, and so freed everyone. A president must understand this aspect of history more than any other. It is our diversity that gives us strength; it is the fight for freedom by the oppressed that frees us all.
And yet, as the Jim Crow era shows, every advance can be rolled back. Reconstruction laws and amendments remained on the books, but white Southern resistance eclipsed their enforcement; only the civil rights movement brought them back to life. A free and fair society depends on shared values, on fragile political norms that have emerged over time. These allow us to disagree and still function peacefully. History holds us together. If we become unmoored from it, I could even imagine a president who repeats Richard Nixon's mistakes, abusing power to obstruct justice, or who falls under the influence of white nationalists.
T.J. Stiles is the author most recently of "Custer's Trials: A Life on the Frontier of a New America," which received the 2016 Pulitzer Prize for History. He lives in Berkeley.