"It’s haunting and a little chilling knowing you’re in the belly of Ground Zero, in the place where so many innocent people lost their lives,” said Lesley Stahl while visiting the 9/11 Memorial & Museum in New York City in 2013, a year before it opened. Alice Greenwald, the museum’s director at the time, explained: “Most museums are buildings that house artifacts. We're a museum in an artifact.” Today marks 24 years since the September 11 terrorist attacks at the World Trade Center — the deadliest terrorist attack on U.S. soil. #60minutes #sept11memorial #sept11