In New Hampshire, Trump elicited ugliness, and he got it. Photograph by Darren McCollester/Getty

“You can make them vicious, violent, horrible questions, even though you’re sort of, probably, on live television,” Donald Trump said to the audience at a campaign event in Rochester, New Hampshire, on Thursday night. He was explaining the format of the event, something that he thought would be more “fun” than a speech—“which I’ve been doing over and over and over”—but the instructions could also be a shorthand for Trump’s theory of campaigning, if not of everyday life. In New Hampshire, he elicited ugliness, he got it, and, to all appearances, he relished it.

“O.K., this man—I like this guy,” he said, calling on the first questioner, who was wearing a Trump T-shirt.

“We have a problem in this country: It’s called ‘Muslim,’ ” the man said. Trump nodded.

The man continued, “You know our current President is one—”

“Right,” Trump said.

“You know he’s not even an American,” the man continued, and at that Trump interrupted again, saying, “We need this question. This is the first question!” The word “first” was subsumed in a Donaldian chuckle—the kind that serves as an ambiguous indicator of both sarcasm and glee.

“But, anyway, we have training camps growing, where they want to kill us,” the man persisted. “That’s my question: When can we get rid of them?”

"We’re going to be looking at a lot of different things,” Trump replied. “And, you know, a lot of people are saying that, and a lot of people are saying that bad things are happening out there. We’re going to be looking at that and many other things.”

Afterward, Trump was widely criticized for not correcting the man, for not acting, in fact, as that “loser” John McCain had, in 2008, when a questioner at one of his rallies described Barack Obama as “an Arab” whom she couldn’t trust. It would seem like the minimal act a decent candidate could undertake. One might ask the other Republicans in the race why they haven’t really found the opportunity to correct Trump—at this point, they’ve been on plenty of stages with him. On Friday, Lindsey Graham said that Trump should apologize for not acting as Graham’s friend McCain did, and Christie said that he would have handled the encounter differently—though he added that he didn’t want to “lecture” Trump. Otherwise, the Republican candidates were slow to speak. Trump is not just someone who stands by when the President’s faith, birthplace, or basic identity are put into question; he pushes that view. As recently as this July, when Anderson Cooper asked Trump if, with all the documentation out there, including a long-form birth certificate, he accepted that the President was born in America, Trump said, “I don’t know. I really don’t know.”

But even more outrageous, this week, was Trump’s tolerance of the questioner’s premise: that Muslims in America are “a problem.” Calling Obama a Muslim is not wrong because being a Muslim is bad; it’s wrong because he is a Christian, and so “Muslim” becomes a shorthand for impostor and liar, for deceptive secret agent. Trump, though, went well beyond not defending the President: he affirmed an attack on the millions of Muslim Americans who are as much a part of the national community as anyone else. The man in the T-shirt’s actual point, after all, was about the supposed training camps “where they want to kill us.” He wanted Trump to answer his question: “When can we get rid of them?”

The campaign did say, according to the Washington Post, that it understood “them” to refer to the “training camps,” not to a potential ethnic cleansing of the Muslim population as a whole. A campaign official also said that Trump was focussed on the part of the question about this larger phantom threat, and not on the part about Obama’s religion—as if entertaining an insult to an entire community, rather than just to the President, were a defense. Trump’s own statement seemed to underscore the man in the Trump T-shirt’s fears: “The media wants to make this issue about Obama. The bigger issue is that Obama is waging a war against Christians in this country. Christians need support in this country. Their religious liberty is at stake.” Donald Trump, Christian warrior.

Last week, in an effort to slow Trump’s momentum, the Club for Growth released ads portraying him as a liberal. Jeb Bush, too, has made the case that the problem with Trump is that he is inadequately conservative—as if, with Trump’s talk of building walls, the G.O.P. were being pestered by a moderate in its midst. Perhaps his comments in New Hampshire will persuade his competitors to confront his extremism instead. So far, they have been too fearful or too eager for the votes of people like the man in the T-shirt. Or maybe they agree; Ben Carson, for one, has talked about the possibility of staged civil disorder leading to the cancellation of elections. (Hillary Clinton, who was also in New Hampshire, said that Trump “should have, from the beginning, repudiated that kind of rhetoric.”)

It can’t be said that Trump didn’t have control of the exchange; he had, after all, broken in twice. And he had another opportunity to do so when, later in the event, another questioner rose to say, “I applaud the gentleman who brought up the Muslim training camps here in the U.S.A.—the F.B.I. knows all about that.” To which Trump replied, again, “right.”

“But America has also guns pointed at ordinary citizens here,” the second man said, and then hesitated.

“Don’t get nervous!” Trump said. “You’re on about seven television networks here—don’t get nervous!"

The man launched into a disjointed attack on the Bureau of Land Management. “How can we get in and stop them?” he said.

“So many things are going to change,” Trump said, and then offered some news-you-can-use for conspiracy theorists.

“Being in real estate, we have Army bases, Navy bases—so many are for sale,” Trump said. “And so many of them have been sold over the last short period of time.”

And just who is buying those military bases? The audience seemed to know. Evan Osnos wrote recently about the support for Trump among white supremacists and other extremists in this country. It can seem, though, as if they are not only listening to him but as if he is listening to them. Trump is learning the practice of politics in halls echoing with American paranoia. There has always been a strain of that, and he is not alone in playing to it: a number of Republican senators solemnly presented themselves as concerned investigators of Jade Helm, a U.S. military training exercise that, in some circles, was presented as a dress rehearsal for martial law. The man in the T-shirt has a theory; the man in the suit smiles. What is less and less clear, in the interaction between the potential Presidents and the crowd, is who is humoring whom.