In an effort to explain why he didn't want to change his schedule to cancel a political rally just hours after 11 people were killed in a shooting at a synagogue, President Donald Trump incorrectly said that the New York Stock Exchange reopened the day after the 9/11 attacks.

"With what happened early today, that horrible, horrible attack in Pittsburgh, I was saying maybe I should cancel both this and that," Trump said Saturday at a rally in Murphysboro, Illinois, for Republican Rep. Mike Bost. Earlier in the day, the president had gone forward with an appearance at the Future Farmers of America's annual convention in Indianapolis.

At the rally, Trump said he remembered that after the attacks that destroyed the World Trade Center on Sept. 11, 2001, "the New York Stock Exchange was open the following day."

The problem: The New York Stock Exchange remained closed until Sept. 17 (which has been deemed "Wall Street's proudest day.")

The president made the misstatement while explaining that he did not want to "start changing around our lives and changing around our schedules" for "somebody that's sick and evil."

Trump said Dick Grasso, "a friend of mine, great guy, he headed up the New York Stock Exchange on September 11th, and the New York Stock Exchange was open the following day."

"He said what they had to do to open it you wouldn’t believe, we won’t even talk to you about it, "Trump explained. "But he got that exchange open. We can’t make these sick, demented, evil people important."

He later continued: "We can't allow people like this to become important. And when we change all of our lives in order to accommodate them, it's not acceptable."

"So, I thought of it for a little while, and the press said, 'Are you going to cancel these two events?' And, frankly, the Future Farmers, I could have done that one. But this is a rally for Mike Bost – and frankly this one, maybe I could have – except I don't want to change our life for somebody that's sick, and evil. And I don't think we ever should."

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