On Thursday, Donald Trump escalated his racist attacks on Gonzalo Curiel, the federal judge hearing one of the fraud cases against Trump University.

The presumptive Republican nominee had already called the judge a “Mexican” — the Latino jurist was born in Indiana — and floated the allegation that Curiel’s ethnicity biases him against Trump because of the candidate’s immigration stance. Trump had threatened to use the power of the presidency against the judge, saying “we will come back in November” and people “ought to look into” the judge. Then, in an interview with the Wall Street Journal on Thursday, Trump said Curiel’s “Mexican heritage” presented “an absolute conflict” in hearing a case against him.

Yet that very afternoon, the highest-ranking Republican official in the land, House Speaker Paul D. Ryan (R-Wis.), endorsed Trump. Incredibly, one of the justifications cited in Ryan’s reasoning was that he had talked with Trump about “the proper role of the executive.” And Trump learned that the proper role of the executive is . . . to threaten a federal judge in an overtly racist attack?

Republicans had better get used to such jarring juxtapositions, now that the party has embraced a man who traffics in racist politics and conspiracy theories.

Ryan’s salute ends any doubt: The GOP is the Party of Trump. Ryan and his colleagues have bet their future, and that of the Republican Party, on Trump, and they now own what the volatile showman says and does. Ryan, after holding out for a month before embracing Trump, folded without any tangible concession. The speaker says he thinks Trump would support the House Republicans’ agenda. But the reverse is already true: The Republican establishment has, with Ryan’s capitulation, made Trump’s agenda their own.

And what is that agenda? Let’s consider some of the theories Trump has floated — and people such as Ryan are, with their endorsements, now countenancing:

Supreme Court Justice Antonin Scalia was murdered.

Rafael Cruz, Ted’s father, was involved in the JFK assassination.

President Obama’s wedding ring is inscribed “There is no god but Allah.”

Bill Ayers wrote “Dreams From My Father.”

Obama was born “Barry Soetero.”

The Hawaii official who verified Obama’s birth certificate was murdered.

Clinton administration official Vincent Foster’s suicide was really a murder.

A demonstrator who rushed the stage at one of Trump’s rallies has ties to the Islamic State.

The Islamic State pays the cellphone bills of Syrian refugees.

Trump is being persecuted by the Internal Revenue Service because he’s a “strong Christian.”

The government has falsified statistics on unemployment, Ebola, refugees, health insurance and immigration.

Global warming is a hoax created by the Chinese.

Vaccines cause autism.

These were among 58 conspiracy theories tallied up last month by People for the American Way, a liberal group, all documented with links to Trump’s allegations. Better make that 59: Just hours after Ryan’s endorsement, Trump disseminated an accusation on Twitter that Hillary Clinton “killed four Americans in Benghazi.” The list goes on: A U.S. general dipped bullets in pig’s blood to shoot Muslims; Muslims in New Jersey celebrated on 9/11; Obama is a Muslim. All that’s missing from Trump’s oeuvre is a theory about Area 51 and fluoridation.

Certainly not everybody who supports Trump supports everything he says. But Ryan and his colleagues, by embracing Trump, are making paranoia and racism — once limited to the dark corners of the Internet — mainstream. They are putting themselves, and their party, behind Trump’s bigotry and conspiracy theories.

They are blessing Trump’s recent attack on one of the few high-ranking Hispanics in the GOP, New Mexico Gov. Susana Martinez, and on his labeling Sen. Elizabeth Warren (D-Mass.) “Pocahontas” because she claimed to have Native American ancestry. The evening before Ryan’s embrace of Trump, the New York Times reported the resignation of the head of Hispanic media relations at the Republican National Committee because of her discomfort with Trump.

They are legitimizing, too, Trump’s attack on Curiel, in which he tries to disqualify a federal judge because of his ethnicity. He referred to the American-born Curiel as “the judge, who happens to be, we believe, Mexican.” This is reminiscent of how he referred to Obama: “We have a terrible president who happens to be African American.”

Surely Ryan and most of his GOP colleagues in Congress wouldn’t allow such talk to cross their own lips. But in endorsing Trump, they have made his vile words the creed of the Republican Party. Win or lose, they have turned the Party of Lincoln into the Party of Trump.

Twitter: @Milbank

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