Notice the top part of WTC Tower above where the plane struck and how it has started toppling to the side. What forces stopped this huge portion of the World Trade Center tower from continuing to rotate away from the structure below. What forces caused this huge top section of this building not to fall to the street in one huge section but instead be turned into a fine white dust with the rest of the building including everything in it.
Common sense tells me that this huge top section was demolished by high-powered explosives. This is the only plausible explanation as to why this section stopped rotating and as to why this section did not fall to the street fairly intact.