Why the Donald Trump who appeared on stage Monday can't win

Here are the best moments of Clinton and Trump's fiery debate
Here are the best moments of Clinton and Trump's fiery debate

If the presidential debate lasted about 10 minutes, Donald Trump could be celebrating a game-changing victory on the morning after.

But it lasted 90 minutes and turned into a compete nightmare for the Republican nominee, who could not stop interrupting his opponent and saying incomprehensibly idiotic things.

For Trump, it all started well enough Monday night, with the New York tycoon putting Democrat Hillary Clinton on the defensive over trade deals and promising to bring manufacturing jobs back to the Rust Belt. Trump was calm and poised and apparently ready to convince people hungry for change that he could actually occupy the Oval Office without being a total embarrassment or grave danger to the world.

"So Ford is leaving. You see that, their small-car division leaving. Thousands of jobs leaving Michigan, leaving Ohio. They're all leaving. And we can't allow it to happen anymore," Trump said, with his sights set on unhappy swing state voters. "We have to stop our jobs from being stolen from us. We have to stop our companies from leaving the United States and, with it, firing all of their people."

Clinton parried Trump on the economy with her first planned zinger of the night, accusing him of promoting "trumped-up trickle down" policies that would favor the rich and explode the deficit.

Donald Trump pauses during the first debate against Hillary Clinton, Sept. 26, 2016.
Joe Raedle | POOL | Reuters

But Trump was at least on Clinton's level during these exchanges. That didn't last very long. The trouble began when Clinton ripped Trump for comments about getting a big loan from his father to start his business career and cheering the housing bubble collapse. Instead of offering a reasoned response, Trump simply interjected "that's called business, by the way."

Then Clinton slammed Trump for calling global warming a hoax perpetrated by the Chinese. "I did not. I did not. I did not say that," Trump complained. Then everyone on Twitter retweeted Trump saying exactly that.

A clearly agitated Trump then began repeatedly interrupting Clinton and continued doing so roughly 50 times during the debate. That's not something that will play especially well with college-educated suburban women who tend to loath "mansplainers" who won't let a woman talk. Ask Rick Lazio how that went in his Senate campaign against Clinton.

Trump never really recovered. He accused Clinton of "fighting ISIS your entire adult life" something that's impossible given that ISIS formed after the Iraq invasion of 2003. And he attacked Janet Yellen and the Fed for "doing political" with its reluctance to raise interest rates.

Then the debate shifted to Trump's refusal to release his tax returns and things got ugly for the Republican nominee. Clinton launched into a litany of things Trump could be hiding, including the fact that he has paid little or no federal taxes for years. Did Trump protest and say of course he pays taxes? No he didn't. "That makes me smart," he said. Undecided voters who dutifully pay their taxes every year probably didn't love that line.

Clinton also ripped Trump for stiffing contractors. Again, Trump didn't even protest.

Instead he offered this when pressed over an unpaid contractor: "Maybe he didn't do a good job and I was unsatisfied with his work."

It got worse. Trump had no answer for why he pushed birtherism for five years after President Barack Obama released his long-form birth certificate other than to double-down on the canard that Clinton somehow "started" the birther controversy even though she never raised it and immediately endorsed Obama after it became clear she couldn't win the nomination in 2008.

Moderator Lester Holt gave Trump an opportunity to explain to Americans, especially African-Americans, why he built his political career around birtherism despite the complete debunking of that particular conspiracy theory. Trump's response: "I say nothing, because I was able to get him to produce it. He should have produced it a long time before. I say nothing."

Trump went on to suggest maybe it was not Russia that hacked the Democratic National Committee despite uniform consensus in the national security community that it was, in fact, Russia. And this was his response on how the U.S. could be better at cybersecurity: "I have a son. He's 10 years old. He has computers. He is so good with these computers, it's unbelievable. The security aspect of cyber is very, very tough. And maybe it's hardly do-able."

Perhaps the worst segment for Trump was when Holt pivoted to gender and asked the GOP nominee about his comments that Clinton doesn't have "a presidential look." Trump ignored the question and instead questioned Clinton's stamina for the job. Clinton pounced. "As soon as he travels to 112 countries and negotiates a peace deal, a cease-fire, a release of dissidents, an opening of new opportunities in nations around the world or even spends 11 hours testifying in front of a congressional committee, he can talk to me about stamina," she said to cheers from an audience that was repeatedly admonished to stay quiet.

Clinton continued to dig the knife into Trump over his comments about women. "This is a man who has called women pigs, slobs and dogs. And someone who has said pregnancy is an inconvenience to employers," she said. "And one of the worst things he said was about a woman in a beauty contest. He loves beauty contests, supporting them and hanging around them. And he called this woman Ms. Piggy. Then he called her Ms. Housekeeping, because she was Latina."

Trump then inexplicably injected Rosie O'Donnell into the final moments of the debate. "I said very tough things to her and I think that everybody would agree that she deserves it and nobody feels sorry for her," he said about his comments that O'Donnell is "disgusting" and "a pig."

Perhaps more incredibly, Trump continued talking about the beauty contest winner on "Fox & Friends" on Tuesday morning bringing up the Miss Universe contestant, Alicia Machado, whom Clinton referenced during the debate. "She was the worst we ever had, she was impossible," Trump said. "She was the winner and she gained a massive amount of weight and it was a real problem."

Trump talking about women and their weight issues is not where he wants to be six weeks before the election with the outcome hinging in part of the GOP nominee's ability to convince suburban women voters that he is a good choice for president.

Overall, the debate was a disaster for Trump, something that became clear as Republicans supporting the nominee spent much of their time after the event complaining about the moderator. Focus groups and polls conducted by CNN and others suggested Clinton won big. That may not be reflected in a massive swing in national or swing state polls in the coming days. But Clinton doesn't need a massive swing. She just needs to reassert her consistent edge.

Trump needed a breakthrough performance to turn his momentum into a real lead. Instead, he was the Donald Trump the nation came to know during the GOP primaries. And that Donald Trump can't win.

— Ben White is Politico's chief economic correspondent and a CNBC contributor. He also authors the daily tip sheet Politico Morning Money [politico.com/morningmoney]. Follow him on Twitter @morningmoneyben.