What did Donald Trump do today?

He invented a brand new lie about his supposed 9/11 heroics to go with all the old ones.

Today, at a ceremony that was supposed to honor fallen heroes of September 11th, Trump unveiled a new and unequivocally false story that put him squarely at the center of the action. Not just supervising literally "hundreds" of Trump Organization employees in a rescue effort—a disproven lie he's told in the past—but personally in danger of death at the U.S. Steel building right next to the collapsed towers. 

TRUMP: And I'll never forget, two firemen—we thought it was coming down on top of us, and two firemen, big strong guys—and I'm not the smallest guy in the world—they grabbed me under the arm, said, 'Got to get out of here!' and they literally lifted me up. This is not easy to do. I'm big. They lifted me up and they started running with me, I said, "Fellas, I can run myself." But they were amazing, but they thought it was coming down. It didn't come down, U.S. Steel.

There is no evidence whatsoever that Trump was anywhere near the World Trade Center site on September 11th or September 12th. The earliest he was anywhere near the site was on September 13th, when he gave the latest in a series of post-attack interviews, this time for a German news outlet. He did not mention the fictitious imminent collapse of the U.S. Steel building then—or at any point in his life until today.

That interview on the 13th was when he claimed to be there supervising Trump Organization workers—"over one hundred… and about 125 [more] coming." This was, and has always been, a lie. No one, including the hundreds of supposed workers, has ever come forward with any evidence. Contrary to Trump's version of the facts, untrained office workers would not have been allowed anywhere near the site, which was incredibly dangerous and an active crime scene. As an NYFD battalion chief at the time put it, if Trump's phantom army of volunteers existed,

There would be a record of it. Everybody worked under direct supervision of the police and fire department and the joint commander for emergency services.  

In reality, by early on the afternoon of September 11, Trump had kicked off a media blitz. He called into a local Fox affiliate to brag that a property he owned, 40 Wall Street, was now the tallest in Manhattan. Even this was a lie: The Empire State Building, the Chrysler Building, and 70 Pine Street were all taller. Trump didn't even own the building: he just held the lease. 

During his post-attack publicity spree, Trump promised the massive audience of the Howard Stern radio show that he would give $10,000—about 0.01% of his supposed net worth at the time—to 9/11 charities. He never did. In 2016, while running for president, he directed his charitable foundation to give $100,000 of other people's money to the 9/11 Museum. (That foundation was later dissolved by court order as a fraud.)

Trump's September 11th story has changed considerably over the years, though never quite as dramatically as today. When he was running on an anti-Muslim platform in 2016, he claimed to have seen television footage of a "large Arab population… thousands and thousands of people" in Jersey City who were "cheering as that building was coming down." This, too, is a lie: literally nobody other than Trump has ever corroborated his story, which would have happened during a time of extreme tension and backlash against Muslim- and Arab-Americans. No such television footage ever existed.

At today's event, Trump also "jokingly" complained that an actual 9/11 hero, the volunteer firefighter Welles Crowther, had "become more famous than me—I don't like it." Crowther, whose identity as the man who ran repeatedly upstairs to guide injured people to safety, died on the day of the attacks. He had helped to save 18 people who were trapped on the upper floors of the South Tower, just below the point of impact.

Welles Crowther, who died on Sept. 11, 2001, after saving the lives of 18 other people

Trump will not attend the official 9/11 memorial in New York City. He is scheduled to leave the country on that day to attend a golf tournament in Ireland. 

Why does this matter?

• The kindest possible interpretation of what Trump dared to say today, in front of the families of actual heroes and victims, is that he is so far gone into dementia that he has no idea what he's saying.