Interesting that the only 3 skyscrapers in history to "collapse" due to fire were at the World Trade Center. Remember the 3rd one? Fell around 5:30p yet it wasn't hit. The owner of the WTC said they decided to "pull" it(ie controlled demolition). It would take weeks to wire a 47 story building for demolition (according to demolition experts). They managed it in a few hours. Interesting.