I do believe that it's the first time in history that fire has ever melted steel. I do believe that it defies physics that World Trade Center tower 7-building 7, which collapsed in on itself-it is impossible for a building to fall the way it fell without explosives being involved. World Trade Center 7. World Trade [Center] 1 and 2 got hit by planes-7, miraculously, the first time in history, steel was melted by fire. It is physically impossible.