Donald Trump is an unflinching critic of anything and everything he finds un-American. On Saturday, he flinched.

We know by now what it looks like when Donald Trump wants to condemn someone. Brit Hume is “a dope” and a “know-nothing.” Mika Brzezinski is “dumb as a rock” and “crazy.” Bill and Hillary Clinton were “the real predators.” Ted Cruz is a “wacko” and “weak.” Chuck Todd—“pathetic” and “very dishonest.” James Comey—“nutjob.” Intel leakers are “low-lifes” and Democrats are “phony hypocrites.” Republicans are “disloyal,” “naive” and “dishonest” while European leaders are “weak.” You get the idea.

Trump is quick to condemn—in specific and harsh terms—anyone he doesn’t like. He’s blunt, he’s direct, and he’s politically incorrect.

So it was striking on Saturday when Trump refused to denounce the white supremacists and neo-Nazis whose public rally in Charlottesville, Virginia, led to violence. The racists marched the streets hauling Nazi flags and torches, chanting, “you will not replace us” and “blood and soil.” They taunted counter-protesters and innocent passers-by.

And yet when their aggressive behavior triggered riots and violence in the streets of the quiet college town, the president declined to condemn them. What he offered instead was a cowardly, irresolute, passive statement criticizing the generic intolerance of unnamed groups.

"We condemn in the strongest possible terms this egregious display of hatred, bigotry, and violence on many sides,” the president said in a live statement. “On many sides."

If this generic, equivocal statement was an anomaly, it might be easier to dismiss. We’d hope it was an oversight and we’d wish Trump were more presidential. But we’ve seen this before.

On February 26, 2016, Trump took questions from the media. A reporter asked the emerging Republican frontrunner about an unsolicited endorsement he’d received from former Ku Klux Klan leader, David Duke. Duke had told listeners of his radio show to volunteer for Trump: "You're gonna meet people who are going to have the same kind of mind set that you have." He said: "Voting for these people, voting against Donald Trump at this point, is really treason to your heritage."

Trump wasn’t happy with the question. "I didn't even know he endorsed me. David Duke endorsed me? Alright," Trump shrugged. "I disavow it, okay?"

Trump’s grudging disavowal drew criticism from a wide variety of politicians and civil rights groups, including the the Anti-Defamation League. Two days later, CNN’s Jake Tapper offered Trump a chance to strengthen his half-hearted disavowal. "Will you unequivocally condemn David Duke and say that you don't want his vote and that of other white supremacists in this election?"

Trump didn’t offer an unequivocal condemnation. He didn’t offer condemnation at all. Instead, he responded with a jumble of half-truths, misdirections and Trumpian tropes meant to avoid any such condemnation.

"Well, just so you understand, I don't know anything about David Duke," Trump said. "I don't even know anything about what you're talking about with white supremacy or white supremacists. So, I don't know. I don't know—did he endorse me or what's going on? Because, you know, I know nothing about David Duke. I know nothing about white supremacists. And so you're asking me a question that I'm supposed to be talking about people that I know nothing about."

Of course Trump knew about David Duke—any casual news consumer over the past twenty years knows about David Duke. In 2000, Trump cited Duke as a reason for his reservations about joining the Reform Party, and seemed to know Duke’s history pretty well. ("Well, you've got David Duke just joined—a bigot, a racist, a problem. I mean this is not exactly the people you want in your party.") More to the point, Trump had been asked about Duke two days earlier and he knew enough to offer a half-hearted disavowal.

Tapper pressed. "I guess the question from the Anti-Defamation League is, even if you don't know about their endorsement, there are these groups and individuals endorsing you, would you just say, unequivocally, you condemn them and you don't want their support?"

"Well, I have to look at the group. I don't know what group you're talking about. You want me to condemn a group that I know nothing about. Look, if you would send me a list of the groups, I will do research on them and certainly I would disavow if I thought there was something wrong," said Trump.

"The Ku Klux Klan?"

"You may have groups in there that are totally fine and it would be very unfair, so give me a list of the groups and I'll let you know."

"Okay, I'm just talking about David Duke and the Ku Klux Klan here."

"Honestly, I don't know David Duke," Trump claimed to Tapper. "I don't know if I've ever met him—I'm pretty sure I didn't meet him. I don't know anything about him."

This exchange wasn’t just a failure to denounce Duke and white supremacist groups; it was a refusal to do so. And Trump’s neo-Nazi footsie brought on even more criticism of the Republican frontrunner.

As always, Trump had an explanation. "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," said Trump on NBC’s Today show the next day . "What I heard was 'various groups.' And I don't mind disavowing anybody, and I disavowed David Duke."

Tapper mentioned David Duke and the Ku Klux Klan twice each, white supremacists once. And Trump repeated the language from the questions in his answers. But, sure, Trump only heard “various groups.”

Why does Trump do this? Is he a racist? Merely sympathetic to the kind of racism embraced by the “alt-right”? Or is it simply his eagerness to criticize people who oppose him and praise—or at the very least, avoid criticizing—those who support him?

Despite—or perhaps because of—Trump’s weak disavowals in the past, white supremacists still think Trump is, at the very least, open to them. At the rally on Saturday afternoon, David Duke said: "We're going to fulfill the promises of Donald Trump." After Trump's remarks, Duke encouraged him to "take a good look in the mirror & remember it was white Americans who put you in the presidency, not radical leftists.”

Other white supremacists are convinced that President Trump is more than just open to them. The white supremacist Daily Stormer ran a liveblog of the Charlottesville rally and they positively celebrated Trump’s refusal to denounce them: “No condemnation at all. . . . When asked to condemn, [Trump] just walked out of the room . . . God bless him.”

President Trump built his reputation with tough talk and harsh condemnations of people who earn his disapproval. That he refused to offer those things on Saturday is no accident.

It's no surprise, either.