Republicans who have sworn allegiance to Donald Trump—the majority leaders of the United States House and Senate, the chairman of the Republican National Committee, and numerous governors and members of Congress—don’t think this country can return to the racism and fascism of the 20th century. They want us to believe that Trump will respect the norms of the post-Holocaust, post-segregation era because they support him. In truth, their capitulation should alarm us. As other countries have learned, the first step in the descent to racism and fascism is to become numb to them. Over the past week, we’ve received fresh evidence that the numbing process is underway.

Since announcing his candidacy, Trump has tested our tolerance. He has insinuated that Cuban Americans, Mexican Americans, and Seventh-day Adventists can’t be trusted. He has proposed a ban on Muslims. These statements have thrilled his crowds, and they haven’t cost him the support of Republican leaders. In general election polls, he has pulled even with Hillary Clinton.

So the assault continues. On Friday, at a rally in San Diego, Trump claimed that the federal judge who is hearing the fraud case against Trump’s real-estate “university” is biased and corrupt—in part, apparently, because the judge is “Mexican.”

Trump has previously portrayed people as biased or untrustworthy, based purely on Latino ancestry, on at least four occasions. Last summer, after retweeting an allegation that Jeb Bush “has to like the Mexican illegals because of his wife,” Trump defended this claim on the grounds that Bush’s wife—who had been an American citizen for more than 35 years—was “from Mexico.” On Dec. 12 and Dec. 29, Trump suggested to Republican audiences in Iowa that they shouldn’t vote for Sen. Ted Cruz because “not too many evangelicals come out of Cuba.” In February, Trump accused Gonzalo Curiel, the judge in the Trump University case, of conspiring against him, calling Curiel “Spanish” and “Hispanic.” When Trump was asked to explain the connection between the judge’s alleged bias and his ethnicity, Trump said: “I think it has to do with perhaps the fact that I’m very, very strong on the border.”

Trump’s attack on Friday continued in this vein. “I have a judge who is a hater of Donald Trump,” he told a crowd in San Diego. “His name is”— at this point, Trump, having raised his voice like a drum roll, held up a piece of paper and pronounced the name carefully, gesturing for effect—“Gonzalo Curiel.” The audience booed, and Trump let the moment soak in, shaking his head in solidarity. Trump told the audience two things about Curiel: that he “was appointed by Barack Obama” and that he “happens to be, we believe, Mexican.” After railing against Curiel and the lawsuit for more than 10 minutes, Trump concluded: “The judges in this court system, federal court—they ought to look into Judge Curiel.”

Trump added, as he often does when bringing up his opponents’ ancestry, that it’s “great” and “fine” to be Latino (or, as Trump prefers to call it, “Mexican”). “I think the Mexicans are going to end up loving Donald Trump, when I give all these jobs,” he predicted. But on Monday, Trump’s spokeswoman, Katrina Pierson, dispensed with his pretense of innocence. She repeated what Trump had suggested in February: that Curiel’s ancestry was the reason for his bias. In an interview with CNN, Pierson explained:

What’s really interesting about this particular judge … is he even mentions on his judicial questionnaire that he was a La Raza Lawyers Association member. This is an organization that has been out there organizing these anti-Trump protesters with the Mexican flags. They are pushing it. These signs have been very apparent. And so Mr. Trump is just stating the obvious. … These criminal protesters who are out there defacing property and attacking police officers, they’re doing so under the guise of an anti-Trump protest with their Mexican flags and La Raza. And this judge is connected to that.

When the CNN interviewer pointed out that Curiel had been born in the United States, Pierson retorted:

I don’t know if he’s Mexican or not. I don’t know his heritage or his descent. The point here is, we keep talking about these anti-Trump protests. And we need to identify who these people are and what they’re doing, because this is not a pro-American group who is out there wanting to get their voices heard. They are out there pushing to destroy, propose anarchy, to stop an American president from running for office.

Let’s recap. At least five times in the past year, the candidate who is now the Republican nominee for president has implied that certain public officials are suspect, or are acting against the national interest, because they or their family members are Latino. This isn’t a complaint about illegal immigrants. It’s not even a dog whistle. It’s a straight-up appeal to prejudice. It’s about the color of your skin, the sound of your last name, and where your ancestors came from.

When Senate Majority Leader Mitch McConnell, House Majority Leader Kevin McCarthy, and other Republican officials endorse Trump, they’re saying, in effect, that this kind of race-baiting isn’t a big deal. Perhaps, like the cowardly politicians who have aided rising demagogues in other countries, they imagine that the great man’s habit of incitement will pass. But the habit doesn’t pass, because it’s a habit and because it’s tolerated. Six months ago, Trump was impugning the faith of Cuban Americans. Now he’s impugning the loyalty of Mexican Americans. If you belong to the National Council of La Raza, a Latino advocacy organization, you’re “connected” to protesters who wave “Mexican flags” and are trying “to stop an American president from running for office.”*

If you can’t imagine a strongman coming to power in this country by mounting an ethnic propaganda campaign against minorities, wake up. This is what it looks like. Pierson, Trump’s mouthpiece, cites the 2011 form in which Curiel, as a nominee to the federal bench, answered questions from the Senate Judiciary Committee. On Page 1, the form asked the nominee to state his place of birth. Curiel answered: “East Chicago, Indiana.” Pierson ignores this answer, shrugging, “I don’t know if he’s Mexican or not.” She skips Curiel’s appointment to the California judiciary by Republican Gov. Arnold Schwarzenegger, reported on Page 14. She also skips the dozen or so pages about Curiel’s 17 years as a federal prosecutor specializing in narcotics, money laundering, and extradition. The titles of his major cases—which focused on drug rings from Jamaica, Canada, and especially Mexico—follow a pattern: Each one starts with “United States v.” and ends with a Hispanic surname: Ramirez, Rodriguez, Villanueva, Perez-Aguilar, Mainero, Ayala, Medina.

Even by Trump’s standards, a jurist who built his career prosecuting Mexican criminals, protecting American sovereignty, enforcing the law, and putting country before ethnicity ought to be regarded as a patriot. Sen. Chuck Grassley, the senior Republican on the Judiciary Committee, essentially acknowledged this in his written queries to Curiel. But Pierson ignores all of that. Instead, she targets Page 4 of the questionnaire, where Curiel lists, among the bar associations to which he has belonged, “La Raza Lawyers of San Diego.” She says this membership makes Curiel complicit in pro-Mexican, anti-American activity.

Here is the mission statement of this nefarious lawyers’ association:

Our purpose is to advance the cause of equality, empowerment and justice for Latino attorneys and the Latino community in San Diego County through service and advocacy. We are dedicated to promoting diversity on both the bench and bar. We support law students with mentorship programs and scholarships.

The National Council of La Raza, which the San Diego group links to as a resource (but is not formally affiliated with), is equally seditious.* “Our mission is to improve [Latinos’] opportunities for success in achieving the American Dream,” says the council. George W. Bush and Sen. John McCain have spoken at its gatherings. So have Bush’s attorney general, Alberto Gonzales; Bush’s former commerce secretary, Carlos Gutierrez; Republican Gov. Brian Sandoval of Nevada; and Sen. Mel Martinez, who was Bush’s housing secretary. Gonzales served on the board of NCLR’s Houston affiliate, the Association for the Advancement of Mexican-Americans.

If Curiel, through his La Raza community organization, can be blamed for people “attacking police officers” and trying to “stop an American president from running for office,” then the same slander can be applied to every Latino Republican who has spoken at a La Raza event and has failed to bow to Trump. Last week, Trump lambasted Susana Martinez, the Republican governor of New Mexico, who has irked him with her criticisms. I haven’t found a connection between Martinez and La Raza. But if Trump’s aides can find a link, given what they’ve done to Curiel, do you doubt that they’ll use it?

Trump’s attack on Curiel is a warning, not just about who Trump is but also about how blasé we’ve become. On Sunday, Trump’s chief strategist, Paul Manafort, and his campaign manager, Corey Lewandowski, were interviewed on major network news shows. Neither one was asked about Trump’s tirade against the judge. Meanwhile, Republican senators shilled for Trump as usual. Overt race-baiting has become normalized.

This is how it happens. It happens when you’re not looking. It happens because you weren’t looking.

*Correction, June 3, 2016: The article originally misstated that the San Diego La Raza Lawyers Association, of which Curiel is a member, is affiliated with the National Council of La Raza. They are not formally affiliated. (Return.)

Read more Slate coverage of the 2016 campaign.