Usually truthers debunk themselves because they are idiots. However, Popular Mechanics had a good analysis of it.
http://www.popularmechanics.com/technology/military/news/1227842
Of course, the biggest tard truthers will just say it is propaganda to hide what really happened.
Yeah, there are so many reasons to believe we were really attacked that day. To insinuate the government was involved is like thinking the sun revolves around the earth.
Garcias.
The book issued by Popular Mechanics is excellent to refer anyone to who has doubts, but is still thinking and open to rational explanations.