Before (and since) 9/11, no steel-framed building had ever collapsed from a fire, so there's no way anyone could have predicted it. But somebody did, and warned Rudy Guliani in the nick of time.
In this interview with ABC news, at 00:44, he says: "We were told the World Trade Center was going to collapse."
This of course begs the question: "Who told him and how did they know?"
The 9/11 whitewash commission, of course, never asked.