President Donald Trump’s attacks on prominent African Americans just before the Thanksgiving break—in which he dubbed LaVar Ball, father of one of the three UCLA basketball players who had been released from custody in China, an “ungrateful fool”—prodded the mainstream news media to once again consider a long-percolating question: Why is he so obsessed with using famous African Americans as political foils? Trump, of course, is an aggressive combatant against enemies of all sorts, but there is something peculiar about the way he goes after African Americans: a greater intensity of grievance, a more visceral call for punishment. On the day he attacked Ball, he also retweeted a comment from a supporter who had lamented, “The ungratefulness is something I’ve never seen before.”

The New York Times seemed loath to call the president a racist. “White House officials deny that the president is focused on race when he comments about sports and athletes,” the Times noted. “But to historians and black activists, the tweets are clear evidence of an attempt by the president to send a message of solidarity to many supporters.” This seemed to be a euphemistic way of hinting at the racist subtext of Trump’s remarks.

Writing in The Atlantic, Vann R. Newkirk II was more forthright, describing Trump as “a savant when it comes to knowing how to harness white resentment and hostility towards outspoken people of color,” with a particular focus on prominent blacks who might fit the racist definition of being “uppity.” In the Toronto Star, Daniel Dale suggested that Trumpis either using racism for strategic purposes, or being instinctively racist himself—or it’s both.”

The argument that Trump is playing to his racist base is true enough, but risks becoming banal unless there is specificity about the particular racism at work. After all, Trump is hardly the first president to appeal to bigotry. In modern times, dog-whistle appeals to anti-black racism have been common, ranging from Richard Nixon’s calls for “law and order” to Ronald Reagan’s evocation of “welfare queens” to George H.W. Bush’s demagogic Willie Horton ad to Bill Clinton’s upbraiding of Sister Souljah.

As vile as this racist pandering was, it all pales next to Trump, whose constant appeals to racism call to mind segregationist leaders like George Wallace more than earlier modern presidents. Those presidents might have sent racially based messages on occasion, usually before an election, but they subsequently governed more moderately, embraced the rhetoric of inclusion, and reached out to blacks voters and lawmakers. Trump is distinctive in wanting to govern only on behalf of his base, which is overwhelmingly white. In tandem, he has launched attacks on African Americans, including Golden State Warriors point guard Stephen Curry, Oakland Raiders running back Marshawn Lynch, ESPN anchor Jemele Hill, and Florida Representative Frederica Wilson. Trump has even picked fights with the civil rights hero Representative John Lewis, saying he was “all talk, talk, talk—no action or results.”

In expending all his energy shoring up his base, Trump offers a particular racial vision. Unlike some white nationalists, Trump doesn’t want an all-white America. He’s willing to tolerate non-whites on a provisional basis, so long as they know their place. This inner logic of Trump’s vision was best expressed by the white-supremacist journal American Renaissance. “Each political party proposes an implicit racial vision,” wrote Gregory Hook in the magazine. “A Trump administration is a return to the America that won the West, landed on the moon, and built an economy and military that stunned the world. Non-whites can participate in this, but only if they accept the traditional (which is to say, white) norms of American culture.”

In this “racial vision” there are two types of Americans: white Americans (who have a natural right to the country and are its default norm) and non-whites (who have a provisional status depending on the sufferance of the white majority). Trump’s political role in this racial vision is to be a kind of national sheriff, the authority figure who has the right to stop and frisk non-whites to make sure they are worthy of staying.

As the national sheriff of white America, Trump was naturally justified in asking for Barack Obama’s birth certificate; after all, Obama is a provisional American who has to prove he belongs. Sheriff Trump also has a right to wag his finger at football players who take the knee in protest of police brutality; as provisional Americans they have to show proper respect for the national anthem. Equally bad are provisional Americans who show ingratitude; Real America (i.e. white America) is doing them a favor by letting them live in their country and sometimes rewarding them with wealth. For them to be ungrateful is the height of disloyalty.

The president’s repeated calls for expressions of black gratitude echo some of the most disturbing themes of American history. As the literary scholar George Boulukos argued in a 2008 monograph, the trope of the “grateful slave” emerged in the eighteenth century as a crucial part of the ideological justification for slavery. Sentimental depictions in literature of thankful slaves helped cement the idea that slavery was beneficial and that people of African descent were naturally servile.

After the abolition of slavery, this cultural stereotype transformed into the expectation that African Americans remain obliging and obedient even when they had achieved success. To do otherwise was to be “uppity.” As Jelani Cobb noted in The New Yorker, famous black athletes and entertainers like Louis Armstrong had to present a public face of apolitical amiability or risk the wrath of white hostility. “Yet the belief endures, from Armstrong’s time and before, that visible, affluent African American entertainers are obliged to adopt a pose of ceaseless gratitude—appreciation for the waiver that spared them the low status of so many others of their kind,” Cobb observed. “Stevie Wonder began a performance in Central Park last night by taking a knee, prompting Congressman Joe Walsh to tweet that Wonder was ‘another ungrateful black multi-millionaire.’ Ungrateful is the new uppity.”

Trump’s eagerness to impugn the loyalty of African Americans is matched by the wide latitude he gives to whites. As Dale notes, when the Pittsburgh Penguins hockey team visited the White House, Trump described them as “incredible patriots.” The team is all white and most of its members are not even American citizens. As University of Southern California sociologist Ben Carrington told Dale, “You can be a white Swede or white Canadian and in Trump’s eyes you can be more of a true patriot than an African American basketball player, because you’re white.”

As Adam Serwer noted recently in The Atlantic, Trump’s presidency makes sense as the after-effect of the Obama era, when many whites felt their traditionally secure place on top of the American ethnic ladder had come under threat. Trump goes after famous blacks as a way of sending a very particular message to those whites: There’s a new sheriff in town, and he is going to keep everyone in their place.