Most Americans who were school-age and above on September 11, 2001 have a "9/11 story" that fits into the wide range of emotions felt that day.
While speaking at a ceremony to mark the 18th anniversary of al-Qaeda's attack on the Pentagon, Donald Trump told his own 9/11 story, which began with him watching CNBC's coverage cut away to footage of the first plane strike's aftermath.
"At first, there were different reports: It was a boiler fire, but I knew that boilers aren't at the top of a building. It was a kitchen explosion in Windows on the World. Nobody really knew what happened," Trump said, recalling "great confusion".
But like so many Trump anecdotes, what he claims to have happened doesn't match the facts. Within 30 seconds of CNBC cutting to a live picture of smoke billowing out of the World Trade Center's North tower that morning, anchor Mark Haines was told that a source who worked in the towers had reported a plane crashing into the building as the cause.
At no point in time does Haines or anyone who was on-air with him mention the possibility of a boiler fire or an explosion at Windows on the World, the restaurant on the tower's top floor.
Trump also repeated something today that he has said on numerous occasions over the years, most recently at a July signing ceremony for legislation to renew the federal 9/11 victims' compensation fund: he claimed to have gone to the site of the fallen towers to help.
"Soon after, I went down to Ground Zero with men who worked for me to try to help in any little way that we could," he said.
Trump said he "spent a lot of time" with 9/11 first responders at that July ceremony, but retired New York Fire Department Deputy Chief Richard Alles contradicted these claims in an interview with the New York Times.
"I spent many months there myself, and I never witnessed him," said Alles, who attended the July event. "He was a private citizen at the time. I don't know what kind of role he could have possibly played."
That afternoon, as first responders desperately searched for fallen colleagues in the burning rubble of the collapsed Twin Towers, the man who would become the 45th president called into a local TV station -- Seacaucus, New Jersey's WWOR -- for an interview with anchors Brenda Blackmon and Rolland Smith.
Asked if the towers' collapse, which killed 2,606 people and destroyed the entire World Trade Center site, had damaged his nearby office tower at 40 Wall Street, Trump prefaced his answer with a mention of the height of his building.
"40 Wall Street actually was the second-tallest building in downtown Manhattan, and it was actually, before the World Trade Center, was the tallest -- and then, when they built the World Trade Center, it became known as the second tallest, and now it's the tallest," Trump said.
Even on that day, Trump couldn't bring himself to acknowledge the truth of the matter, which was that a building at 70 Pine Street topped his own structure by 25 vertical feet.
Nine years later, he'd making even bigger false claims by having his then-lawyer direct the National Enquirer to start pushing the lie that former President Barack Obama was not born in the United States.
Seven years after that, he'd be sworn in as president and tell the first of the reported 12,019 false or misleading claims he'd made over the first 928 days of his term.
And nearly two decades after the day that the New York Fire Department Deputy Chief didn't see him at Ground Zero, we still have reason to question the stories he tells us.