some have said, "That 757 couldn't have melted into the WTC the way it did on that day - imagine throwing a tin can through a brick wall. It should have crumpled up and bounced off." to which I say (visually):
shows that the WTC was mostly glass. Tin cans (especially tin cans full of passengers, kerosene, cargo, tonnes of other aeroplane ephemera LIKE ROLLS ROYCE ENGINES and a momentum quotient afforded by 500mph*) go through glass. Mark my words.
Real planes hit the WTCs on 9/11, now we need to investigate whether they were being flown by remote control on the day or by some really bad Cesna trainee-pilots*.
*I cover the confounding factor of Dutch Roll and the potential of installed guidance beacons at WTC 1 and 2, in an earlier post.