For months, as Donald Trump developed his political repertoire, he adopted an uncharacteristic reply for questions about fascism and the Ku Klux Klan: silence, or something close to it.

He used the technique as early as last August, when his opponents, and the press, still generally regarded him as a summer amusement. On August 26th, the Bloomberg Television anchor John Heilemann brought up David Duke, the former Klan Grand Wizard, who had said that Trump was "the best of the lot” in the 2016 campaign. Trump replied that he had no idea who Duke was. Heilemann asked if Trump would repudiate Duke’s endorsement. "Sure,” Trump said, “if that would make you feel better, I would certainly repudiate. I don't know anything about him." Changing tack, Heilemann pressed Trump about an article in this magazine, which described Trump’s broad support among neo-Nazis, white nationalists, and other members of the far right who were drawn in by his comments about Mexicans. Trump maintained a posture of indifference. “Honestly, John, I’d have to read the story. A lot of people like me.” The interview moved on to other topics.

It should be noted that Trump’s unfamiliarity with Duke is a recent condition. In 2000, Trump issued a statement that he was no longer considering a run for President with the backing of the Reform Party, partly because it “now includes a Klansman, Mr. Duke.”

Throughout last fall and into the winter, Trump continued to accumulate support among white nationalists. In November, on a weekend in which he said that a black protester, at a rally in Alabama, deserved to be “roughed up,” Trump retweeted a graphic composed of false racist statistics on crime; the graphic, it was discovered, originated from a neo-Nazi account that used as its profile image a variation on the swastika. In January, he retweeted the account "@WhiteGenocideTM," which identified its location as "Jewmerica.” Shortly before the Iowa caucuses, a pro-Trump robocall featured several white supremacists, including the author Jared Taylor, who told voters, “We don’t need Muslims. We need smart, well-educated white people.” Each time Trump was asked on Twitter about his white nationalist supporters, the candidate, who is ready to respond, day or night, to critics of his debating style or his golf courses, simply ignored the question.

Only under special circumstances did Trump summon a forceful response on matters of the Klan: in January, BoingBoing unearthed a newspaper report from 1927 on the arraignment of a man with the name and address of Donald Trump's father; the story was about attendees of a Klan rally who fought with police, though it wasn’t clear from the story why the Trump in the piece was arrested. Asked about it, Donald Trump denied that his father had had any connection to a Klan rally. “It's a completely false, ridiculous story. He was never there! It never happened. Never took place."

But recently, as Trump’s campaign has received much belated closer scrutiny, his reliable approach to the Klan problem has faltered. On Thursday, Duke offered his strongest support for the candidate yet, telling radio listeners that a vote for one of Trump's rivals would be "treason to your heritage.” The next day, when Trump had hoped to focus on his endorsement by Governor Chris Christie, of New Jersey, a reporter shouted a question about Duke’s embrace, and Trump said, "David Duke endorsed me? O.K., all right, I disavow. O.K.?" For the moment, it worked, and the press conference moved on. Christie, in fact, bore the brunt of the Duke association: he appeared on the front page of the Daily News on Saturday, as the “MAN WITH A KLAN,” with his picture beside a group of hooded Klansmen. In a different spirit, the Daily Stormer, a neo-Nazi news site that long ago endorsed Trump, awarded Christie the title “Heroic Deputy.” (Christie’s overnight evolution from trashing Trump to obeying him repulsed even the political class, a group that is usually more forgiving of self-rationalization. The technology executive Meg Whitman, who had been one of Christie’s top backers, called his alliance with Trump “an astonishing display of political opportunism,” and asked Christie’s donors and supporters “to reject the governor and Donald Trump outright.”)

Over the weekend, Trump’s purported indifference to support from white supremacists and fascists became an inescapable problem. He had retweeted a Mussolini quote from @ilduce2016 (which, it turned out, was an account created by Gawker to trap Trump)—“It is better to live one day as a lion than 100 years as a sheep”—and, when asked, on NBC, if he wanted to associate himself with Mussolini, he said that he wanted "to be associated with interesting quotes.” He added, "Mussolini was Mussolini. . . . What difference does it make?" On CNN, Jake Tapper pressed him about David Duke, and Trump, seeming to forget that he had given a one-line disavowal, reverted to a position of theatrical incomprehension: "Just so you understand, I don't know anything about David Duke, O.K.?" Tapper asked three times if Trump would denounce the Klan’s support, and each time Trump declined. "I don't know anything about what you're even talking about with white supremacy or white supremacists," he said. "So I don't know. I don't know—did he endorse me, or what's going on? Because I know nothing about David Duke; I know nothing about white supremacists."

By Monday, less than twenty-four hours before primary voting on Super Tuesday, his non-answers about the Klan were creating a crisis, and Trump introduced a new explanation: audio trouble. "I'm sitting in a house in Florida with a very bad earpiece that they gave me, and you could hardly hear what he was saying,” he said on the “Today” show. “But what I heard was various groups, and I don't mind disavowing anybody, and I disavowed David Duke and I disavowed him the day before at a major news conference, which is surprising because he was at the major news conference, CNN was at the major news conference, and they heard me very easily disavow David Duke."

There may be no better measure of the depravity of this campaign season than the realization that it’s not clear whether Trump’s overt appreciation for fascism, and his sustained salute to American racists, will have a positive or negative effect on his campaign. For now, his opponents are rejoicing. Marco Rubio, the Florida senator, pronounced him “unelectable.” Governor John Kasich, of Ohio, called Trump’s comments "just horrific." But it is by now a truism to note that Trump has survived pratfalls that other politicians have not. A surprisingly large portion of Americans believed him when he pushed a racist campaign denying the birthplace of Barack Obama; a comparably chilling portion of Americans were attracted when he called Mexicans rapists. By the end of the day on Sunday, he had received the endorsement of Senator Jeff Sessions, of Alabama, the first sitting senator officially to line up with Trump. Sessions was not likely to be bothered by Trump’s flirtations with the Klan. In 1986, he was rejected from a federal judgeship after saying that he thought the Klan was “O.K. until I learned they smoked pot.”

In the weeks to come, Trump is virtually guaranteed to accumulate additional endorsements from politicians like Christie and Sessions, who have divined their interests in drafting behind the strongest candidate for the Republican nomination. Whether driven by fear of irrelevance or attracted by the special benefits of being an early adopter, Christie seemed compelled to do it, and now the remnant of his political reputation is going from a solid to a gas. But the true obscenity of his decision, and those of other Trumpists, may take years to be fully appreciated. In an editorial last week, the Washington Post declared that “history will not look kindly on GOP leaders who fail to do everything in their power to prevent a bullying demagogue from becoming their standard-bearer.” That’s true, but history will judge even more harshly those who stand with Trump now that it is indefensibly clear with whom they are standing.