Actually it wasn't the government entirely. My aunt used to work with Donald Trump. Trump wanted the space to build the tallest, most modern, and luxurious skyscraper in NY. He had bribed Mayor Giuliani to get his "crews" past security, and plant the explosives. He paid the hijackers to crash the planes as a cover. This thing goes farther than you can imagine, but if you had access to Trumps accounting records you would see the massive withdrawal of money in 1 yr leading up to 9/11. My Aunt was uncovering a lot of incriminating evidence, and was about to schedule an interview with Anderson Cooper when mysteriously she disappeared. 2 yrs later, and they still haven't found a body. Trumps plan didn't work out. He thought he was going to be able to purchase the space to build on, and be able to bring in over a 2 billion a yr in leases in the new buildings.