I don't think there is any proof of this actually happening. There are a lot of strange coincidences that can either be ignored or turned into a conspiracy theory. The video chevy posted shows that there was an order given to fire on commercial aircraft by the president, that the fighter planes did not make it on time and that Chaney was aware of the situation. Exercises the same day, selling of large amounts of shares before attacks, there are a lot of these bizzare coincidences that don't really add up to hard evidence. Things like this have been faked before but not on this scale. If these poloticians are making this much money off of this stuff, you have to wonder why they even bother anymore.