"I want them to talk about racism every day."

That is White House chief strategist Steve Bannon’s deepest wish about the Democratic party, according to an interview with The American Prospect’s Robert Kuttner.

“If the left is focused on race and identity, and we go with economic nationalism, we can crush the Democrats.”

It’s a bit hard to interpret what Bannon’s saying here. Does he think that emphasizing racial issues is a losing approach to campaigns, that the party that does it will suffer, and that both Democrats and Republicans would perform better by talking exclusively about the economy? Or does he mean that he wants Democrats to bring race up, because Bannon thinks that when race is the topic at hand, the result is a public backlash to racial tolerance, which benefits the President?

If the latter is what Bannon means, then he might not be wrong. There’s a substantial body of research in political science and political psychology suggesting that even very mild messages or cues that touch on race can alter political opinions.

The landmark book on the subject is Princeton professor Tali Mendelberg's 2001 book The Race Card, which marshaled a wide array of evidence to show that implicit racial messages are used with shocking regularity by American politicians, and have real effects.

Mendelberg looks back to George H.W. Bush’s 1988 attacks on Michael Dukakis for furloughing murderer Willie Horton, which weren’t explicitly racial, but she argues compellingly that tying Dukakis to a black murderer successfully appealed to white voters who already held racially conservative views.

Mendelberg also runs her own experiment to explore the idea. She conducted a study with a random sample of Michigan voters where she showed fake television news stories about a gubernatorial race; in the stories, the conservative candidate was arguing that welfare recipients were an unfair burden. Some of the fake stories featured B-roll of black welfare recipients; others featured B-roll of white recipients. They were otherwise identical — but the stories with B-roll of black recipients led respondents to express significantly more hostile views toward government programs to assist black people. In fact, the effect on their expressed racial views was stronger than the effect on their expressed opinions on welfare.

But the cues can be subtler still, as other research points out. Nicholas Valentino, Vincent Hutchings, and Ismail White manipulated a 2000 campaign ad by George W. Bush that wasn't even about welfare — it was about health care and taxes — by adding imagery of black people counting money, or a white nurse assisting a black mother, while a narrator says, "He'll reform an unfair system that only provides health care for some." In their control group, which saw no ads, measured levels of racial resentment didn’t do much to predict support for Bush versus Gore. Among people who saw the ad with racial cues, their preexisting level of racial resentment was hugely predictive of their presidential preference.

My favorite study on this topic comes from Harvard political scientist Ryan Enos. He sent pairs of native Spanish-speaking Latino men to ride commuter trains in Boston, surveyed their fellow riders' political views both before and after, and also surveyed riders on trains not used in the experiment as a control.

"The results were clear," Enos wrote in a Washington Post op-ed. "After coming into contact, for just minutes each day, with two more Latinos than they would otherwise see or interact with, the riders, who were mostly white and liberal, were sharply more opposed to allowing more immigrants into the country and favored returning the children of illegal immigrants to their parents’ home country. It was a stark shift from their pre-experiment interviews, during which they expressed more neutral attitudes."

Dwell on that. Merely being in the presence of Latino people changed liberal voters’ attitudes on immigration. That’s among the most subtle cues imaginable. And this is a study conducted in the field, among real people, not in a lab.

Now let’s talk about the Trump administration.

People take their opinions from elites — and Trump is a political elite now

All of this research suggests that priming white people to so much as think about race, even subconsciously, pushes them toward racially regressive views. So consider the fact that the constant racial controversies of the Trump administration are going to keep racial issues in the news, and on the minds of white Americans.

The optimistic read is that this will disgust Americans who want unity and progress — they also elected Barack Obama, and by a wider margin, didn’t they? The less optimistic read is that by putting the issue at the forefront of everyone’s consciousness, the controversies will drive white people to become more hostile to black, Latino, and Muslim people.

This is a particularly concerning point given the voluminous body of political science research indicating that people take their policy views largely from elites. UC Berkeley political scientist Gabriel Lenz's book Follow the Leader makes this point in great detail, and it’s been powerfully illustrated in recent experimental work by Stanford’s David Broockman and Washington University in St. Louis’s Daniel Butler.

Broockman and Butler got a number of state legislators to randomly send out letters to constituents; some explained a policy position of the legislator in detail, some only briefly and with minimal justification, and the others were neutral controls. They also surveyed the constituents receiving the letters, both before and after. They found that receiving letters often led constituents to adopt their representative’s opinion, even when they had disagreed before.

This inverts our normal understanding of politics. We tend to think politicians are poll-obsessed creatures who follow public opinion. In fact, they are often trusted authorities who lead public opinion. Think of the Republican Party turning its voters against the individual mandate, an idea conservatives had come up with, or the Obama administration carrying out drone wars that would have shocked liberals if they had been conducted by George W. Bush.

And now that Trump, the most covered politician in the country, is overseeing a series of racial controversies, it seems likely that his supporters, and Republicans in general, will respond like Lenz, Broockman, and Butler have found they do: by adopting their preferred candidate’s views as their own. By following their leader.

Take Trump’s response to Charlottesville. His opponents will point out, correctly, that it is racist. But the research on elite opinion and mass opinion suggests that people who voted for Trump will hear his denials, and his counterattacks, and progressively become more and more okay with more and more troublesome racially biased policies and statements, until by the end of his administration they’re expressing more racially retrograde views than they started with. And that could effect a shift in public opinion that damages politics for years.

More broadly, Trump’s racial controversies — and the justifiably outraged reactions of Democrats and other political opponents — are going to keep issues of race salient in a way they weren’t under the Bush or even Obama administrations, both of which took pains to avoid blow-ups on issues of race. Under Trump, race will stay in the headlines, at the forefront of political debates, on news chyrons, just as it was throughout the 2016 election.

If merely thinking about race pushes white people, even liberal white people as in the Enos study, to be more racially resentful, that could have major consequences even outside a rally-around-the-leader effect. The issue being a persistent topic at all could produce a more racially resentful white electorate.

Is Trump too explicit in his racial provocation to really capitalize on it?

Happy #CincoDeMayo! The best taco bowls are made in Trump Tower Grill. I love Hispanics! https://t.co/ufoTeQd8yA pic.twitter.com/k01Mc6CuDI — Donald J. Trump (@realDonaldTrump) May 5, 2016

One reason for optimism is that Mendelberg and other researchers have often found that explicit racial appeals — for example, mentions of not just the undeserving poor while imagery of black people rushes by, but of undeserving black poor people — are less effective than implicit appeals.

The reason is that people have internalized a pretty strong norm that they’re not allowed to express open antagonism toward black people, or explicitly racist views. “The social prohibition against making racist statements in public acts as a constraint against playing the race card in a recognizable fashion,” Mendelberg writes. “Violating this norm is costly for Republicans … it is costly even with their core constituency of racially resentful whites.”

In fact, Mendelberg argues that this makes calling attention to implicit racial appeals a power tool for anti-racist activists. When Jesse Jackson pointed out that Bush’s Willie Horton attacks were tinged with racism, it turned the implicit racial appeal of Horton into an explicit one and lessened the attack’s effectiveness. In other words: People can fight racism by pointing out that racist stuff is racist.

Trump’s appeals are pretty explicit, by these standards. During the campaign, he wasn’t oblique about the danger of terrorism and immigration, but talked about Muslim people and “rapist” Mexicans specifically. That should, in theory, lessen the attack’s effectiveness.

This view isn’t unchallenged in political science. One notable critique of Mendelberg’s work agreed that implicit racial appeals can work, particularly with less educated voters, but argued that explicit appeals work just as well. But it offers reason for hope.

So does the research of UC Irvine’s Michael Tesler, a leading scholar of race and public opion. Then again, Tesler has found that Trump’s unpopularity could be reducing the public’s attraction to his more out-there racial views.

Support for the border wall actually fell during the 2016 campaign, for instance, including in polls tracking the exact same individuals. Public attitudes to Muslims also improved during the campaign. Tesler calls this “trickle-down tolerance,” and there’s a surprising amount of evidence for it, even overseas; there’s reason to believe disgust with Trump might have contributed to UK Prime Minister Theresa May’s surprisingly weak electoral showing in the June election.

“I actually think Trump's unpopularity will help liberalize racial attitudes in the long-run,” Tesler says. “The problem for racial divisions, though, is he also polarizes attitudes about things where there should be consensus, like condemning white supremacists and that could lead to a revival of overtly racist beliefs.”