Remember Building 7
How quickly we forget.
Check out this website about 9/11, and in particular building 7.
Building 7 was not hit by a plane, and it was said to have fallen because of fire, which is impossible for that type of building. Buildings don't just collapse into their own footprint. That can only be achieved using a controlled demolition.
Controlled demolitions take weeks (and maybe even months) to plan, and setup.
Building 7 was a controlled demolition, and 9/11 was an inside job.