They weren't incapable of learning how to fly a plane because they were trained on U.S. bases and given VISAS by the CIA.
Physics suggests that it would take the path of least of resistance but all three towers took the path of most resistance.
Nanothermite is an explosive. You can't accidentally find it anywhere except where it has been used.
Change this and that and try again. Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit. Cras mattis consectetur purus sit amet fermentum.