The New Phenomenon of Steel Buildings Crushing Themselves
The seven World Trade Center buildings were in the two blue regions of the map to the right. On September 11th, all 7 buildings were destroyed. 110-story WTC 1 and 2, and 47-story WTC 7 were leveled, and WTC 3, 4, 5, and 6 were severely damaged, with large portions of WTC 3, 4, and 6 being crushed.
It is interesting that, in spite of the thorough devastation of all the buildings with World Trade Center addresses, no large buildings outside the blue zones were sufficiently damaged to warrant their demolition in the months that followed the attack. 1 The "collapse" of Building 7 was remarkably tidy. Although it was wedged between the Verizon building and the U.S. Post Office building, it barely damaged either of them.
It is even more interesting that, prior to September 11th, no steel framed building had ever undergone total collapse due to any cause or combination of causes other than controlled demolition and severe earthquakes. Such buildings have survived hurricanes, severe fires, earthquakes, and bombings, but none have fallen down of their own weight -- an event that was portrayed as inevitable on September 11th.
Of the collapses of the three huge buildings on September 11th, the collapse of Building 7 is treated separately. If you believe the official story, then Building 7 would be the only example in history of a steel framed building undergoing complete collapse as a result of fires. It and the Twin Towers would be the only permanent vertical steel structures to have fallen into themselves instead of falling over, except in cases of demolition.
The collapses of the Twin Towers are analyzed in much more detail than Building 7 because there is more evidence, and because, whereas Building 7's fall looked like a standard building demolition, the disintegrations of the Twin Towers had many features that are not easily explained.