What makes Donald Trump such a singular figure — in modern politics and, perhaps, ever — is his refusal to take ownership of the outrageous things he has said and done.

It is the essence of his leadership style, the defiance that exasperates his foes and makes his supporters love him all the more. The one thing that is consistent about him is inconsistency.

Not only does Trump refuse to apologize, he blames others for his own actions. His campaign staff may claim to speak for him, but he will leave even his aides twisting when it suits his purposes.

Never had the GOP nominee done all of this in such a fun-house-mirror fashion as on Friday, when he disavowed a crackpot con that he had once promoted. He even went so far as to claim credit for rectifying the situation.

“Hillary Clinton and her campaign of 2008 started the birther controversy. I finished it,” Trump said, falsely, in an appearance at his newly opened luxury hotel, which is just a few blocks from the White House on Pennsylvania Avenue NW. “President Barack Obama was born in the United States. Period.”

Donald Trump spent a lot of time raising doubts over President Obama's birth certificate in 2011. He finally admitted Obama was born in the U.S. on Sept. 16, but falsely accused Hillary Clinton's campaign of starting the rumor. (Peter Stevenson/The Washington Post)

Trump was referring to the false, racism-tainted theory that the nation’s first African American president was born outside the United States and, therefore, is not a legitimate occupant of the Oval Office.

The impulses of the former “Celebrity Apprentice” host are those of a showman, not a traditional politician encumbered by a record and a governing philosophy.

“There is something of the reality-TV culture in this. What’s going on right now is all that really matters,” conservative intellectual Yuval Levin said.

That was the same instinct for expedience that led Trump earlier this year to revive long-discredited theories that Clinton White House official Vince Foster had been murdered, and to speculate that the father of his GOP primaries opponent, Sen. Ted Cruz (R-Tex.), had somehow been mixed up in the assassination of President John F. Kennedy.

“I fully think apologizing is a great thing, but you have to be wrong,” Trump told “Tonight Show” host Jimmy Fallon a year ago. “I will absolutely apologize sometime in the distant future if I’m ever wrong.”

Instead, Trump just moves on, without a backward glance at the many pronouncements and positions that he has left by the roadside when he no longer finds them useful.

His unsubstantiated theories also delve into serious policy questions.

Republican presidential nominee Donald Trump falsely claimed on Sept. 16 that Hillary Clinton was responsible for starting the birther movement that accused President Obama of lying about his birthplace. (The Washington Post)

On Monday, for instance, Trump told CNBC that Federal Reserve chair Janet Yellen has been keeping interest rates “artificially low” and creating a “false stock market” to make Obama look good.

“She’s obviously political and doing what Obama wants her to do, and I know that’s not supposed to be the way it is,” Trump said. “She should be ashamed of herself.”

Friday was not the first time Trump had falsely claimed that Clinton had been responsible for the lie that had been perpetuated about Obama’s birthplace.

“You know who started the birther movement? You know who started it? Do you know who questioned his birth certificate, one of the first? Hillary Clinton. She’s the one that started it. She brought it up years before it was brought up by me,” Trump said during an interview with CNN’s Wolf Blitzer in May.

It was typical of Trump to justify his own transgressions with the argument that someone else had done it first.

But, in fact, Clinton has never made any such claim, although some in her 2008 primary campaign organization had argued for talking more about her rival’s diverse background and the fact that he had spent part of his childhood in Indonesia. The recommendations were rejected.

Trump’s accusation also glosses over the fact that the rumor has largely taken root within his own electoral base, and that his political rise had been fueled by his zealous cultivation of the Republican Party’s fringe elements.

Trump even claimed in 2011 to have sent a team of investigators to Hawaii, to discover whether Obama had really been born there, as he — and all the public records — attested.

“I have people that have been studying it, and they cannot believe what they’re finding,” Trump said at one point.

In the latest Washington Post-ABC News poll, more than a quarter of Republicans and one-third of those who identified themselves as tea party supporters said that they believed Obama was born overseas, compared with only 19 percent of independents and 12 percent of Democrats.

Rarely, if ever, has a candidate so regularly undercut the credibility of his political handlers. “Don’t believe the biased and phony media quoting people who work for my campaign. The only quote that matters is a quote from me!” he tweeted in May.

As recently as late Wednesday, he had refused to say whether he believed Obama was born in the United States, and had shrugged off his campaign manager Kellyanne Conway’s public statements that he did.

“It’s okay,” Trump said of Conway. “She’s allowed to speak what she thinks.”

To Trump and his supporters, his refusal to apologize is yet another measure of his strength as a leader. He wears the scorn of a legion of media fact-checkers as a badge of authenticity.

Before he made his brief statement about Obama’s birthplace on Friday, Trump basked in the testimonials of the Medal of Honor recipients assembled by the campaign at the hotel.

“We do not need any more bureaucratic leadership from Washington, D.C. We need true leadership from the top. Mr. Trump has never failed in anything, because he listens to his advisers, he listens to his people,” said Mike Thornton, who had received the medal for saving his commander’s life during the Vietnam War.

“For the last eight years, our president hasn’t listened to anybody,” Thornton added. “We cannot stand for four more years of leadership like that. We need somebody who’s going to lead from the front like Donald Trump.”

But, as Trump inspires his supporters, he has also given the other side a new dose of motivation. His comments in Washington came as the Congressional Black Caucus Foundation was gathering for its annual legislative meeting.

“One of the things that we all are used to in this business is dog whistles, but the thing that we’re not used to, and I’m finding it very difficult to getting used to , are the howls of wolves,” Rep. James E. Clyburn (D-S.C.), the dean of the caucus, said at a news conference.

He and other caucus members said that Trump had served to remind African American voters what is at stake in November.

“We’re going to vote and send a message,” said Rep. Brenda Lawrence (D-Mich.). “Not only to the United States of America but to the world that is looking at us.”