The Democratic presidential nominee spoke at a campaign rally in Sanford, Florida, and discussed the importance of tackling terrorism — as well as her readiness to lead.
"I know what happened not far from here at Pulse nightclub in Orlando, I was in New York City on 9/11 as one of the two senators," Clinton told supporters. "I will defeat ISIS."
Clinton, then a senator, was in her Washington, DC, home during the terrorist attacks of Sept. 11, 2001. She spent the day with other members of Congress in the Capitol, and returned to New York the next day.
A photo taken in the aftermath of the attack showed her wearing a dust mask at Ground Zero on Sept. 12, along with Sen. Charles Schumer, Gov. George Pataki, Mayor Rudy Giuliani, and New York Police Department Commissioner Bernard Kerrick.
"After a long, sleepless night in Washington, I flew to New York with Chuck Schumer, my partner in the Senate, on a special plane operated by the Federal Emergency Management Agency," Clinton wrote in her book, Hard Choices. "The city was in lockdown and we were the only ones in the sky that day, except for the Air Force fighters patrolling overhead."
The Clinton campaign did not immediately respond to a BuzzFeed News request for comment.
In her book, Clinton described the horror she felt from the terrorist attacks as well as her sense of responsibility to helping New Yorkers.
She caught the last train back to Washington that night, she wrote.
"[The damage] was crushing," she wrote. "New Yorkers were going to need a lot of help to recover, and it was now our job to make sure they got it."