There’s nothing new in American politics about the racial hostility President Trump has demonstrated this week. The United States was founded on the notion that all men were created equal — with the important constitutional exception that blacks held as slaves should count only as three-fifths of a person for power-distribution purposes. The politics of racism have evolved over the past 200-odd years, as has its overlap with partisan politics. But racism has always been there, as have appeals to issues of race for political purposes.

In recent years, though, it’s been rare to see an elected official as prominent as the president of the United States make as overt an appeal to racial politics as Trump’s in recent days. Trump’s willingness to verbalize that undercurrent has made it much more prominent in the political conversation — and much more common.

We can trace Trump’s rhetoric backward fairly easily. His entry into national politics was largely predicated on his elevation of the lie that President Barack Obama wasn’t born in the United States. It demonstrated to Trump that there was both an audience for and attention to be gained from tapping into rhetoric centered on race.

Seven years ago Thursday, for example, Trump tweeted a story from the conspiracy-hawking website WorldNetDaily aimed at restoking birtherism in advance of Obama’s 2012 election.

This lesson was instructive as he launched his 2016 campaign, beginning his remarks by impugning immigrants from Mexico as criminal by default.

But Trump wasn’t making that idea up. He was mirroring rhetoric from right-wing media, such as Breitbart News. In fact, he was tapping into some of the same concerns that powered the tea party movement, a conservative political insurgency that erupted after Obama’s inauguration.

Researchers Vanessa Williamson, Theda Skocpol and John Coggin, looking at how the tea party shifted the way in which conservatives approached politics, noted the centrality of immigration to adherents.

“We find this concern about immigration to be central to Tea Party ideology,” they wrote in a 2011 report. “Nationally, 80 percent of Tea Party activists see illegal immigration as a very serious problem, compared to 60 percent of Americans overall.” The opposition was often couched in concerns about the extent to which immigrants might use government resources for which Americans would have to pay — a concern that Trump’s administration has echoed.

The researchers pointed to other research, too. One study found that “fears of immigration are closely linked to the ethnic identity of the immigrants in question.” Another determined that “ ‘support for the Tea Party remains a valid predictor of racial resentment,’ even after accounting for ideology and partisanship. That is to say, though many opponents of the social safety net tend to hold negative views of racial minorities, Tea Partiers espouse views more extreme than those offered by other conservative Republicans.”

This undercurrent goes back further, of course. George H.W. Bush’s 1988 campaign against Democrat Michael Dukakis featured an ad decried at the time as nakedly appealing to racial fears. That ad was created by strategist Lee Atwater who, while working for Ronald Reagan in 1981, explained the theory behind it: Instead of explicitly using racial slurs to appeal to race, by 1968 the party would talk about “forced busing, states’ rights, and all that stuff” — eventually shifting to “talking about cutting taxes, and all these things you’re talking about are totally economic things and a byproduct of them is, blacks get hurt worse than whites.”

" ‘We want to cut this’ is much more abstract than even the busing thing,” he said, “and a hell of a lot more abstract than” the n-word.

Atwater was later chairman of the Republican Party.

The reference to 1968 is important. Atwater was describing the “Southern strategy,” the effort to help Richard M. Nixon win the South by quietly elevating racially contentious issues. It was an offshoot of the shifts made during the Civil Rights movement, an effort to entice Southern states that had swung away from the Democratic Party after its embrace of the Civil Rights Act in 1964 without explicitly using racism as the lure.

This is the history into which Trump tapped. His willingness to dive fully into anti-immigrant and racially divisive rhetoric paid off. After his campaign announcement claims about Mexican immigrants spurred a broad backlash, his stock with a segment of the Republican primary electorate surged. It built that core of support that pushed him through the early primaries.

The political utility of those views was obvious to Trump — which isn’t to say that he doesn’t sincerely hold them. Trump once compared the nativist politician Pat Buchanan’s politics to the Nazis but in January embraced a Buchanan editorial that championed Trump’s immigration policies.

Since he jumped into the race, Trump’s explicitness on race and immigration has caused similar concerns and attitudes to pop into view elsewhere. That was obvious Wednesday night, when attendees at a Trump rally responded to his sweeping condemnation of a Muslim member of Congress who’d immigrated to the U.S. with cries of “send her back.”

Research by Tufts University’s Brian Schaffner found a link between Trump’s rhetoric and a willingness to express racist comments publicly.

“[I]ndividuals who were exposed to Trump’s quote about Mexicans” — the one from his campaign announcement — “were significantly more likely to make negative and offensive remarks not only about Mexicans, but also about other identity groups such as blacks and millennials,” his research found.

In polling released this week, Pew Research Center found an increase since 2017 in the number of Republicans who say that America “risks losing [its] identity as a nation” if the country is too open to immigration. (There hasn’t been a change among Democrats.)

Trump’s also driving conservative media. Before his campaign announcement, there wasn’t a lot of discussion of immigrants and crime on cable news. After, crime was much more frequently a context in which migration was discussed.


(Philip Bump/The Washington Post)

But that's largely a function of how often Fox News talked about it.


(Philip Bump/The Washington Post)

Fox talked about immigration in the context of crime seven times as heavily in the four years after Trump’s campaign announcement than in the four years prior.

Trump didn’t create the racial tension, resentment and concern that’s been present in right-wing politics. But he benefited from it. He’s amplified it. He’s helped surface it.

As this week has made clear.