I happened onto a "911 truth" website, and promptly found out that it was an A-3 Skywarrior ("Whale") that crashed into the Pentagon on 9/11, not a 757 airliner. This A-3 Skywarrior apparently flew off the carrior U.S.S. George Washington, which was docked in New York Harbor on 9/11.
Where to start, where to start... okay. First of all, the A-3 was retired in 1991. There are none in military service. Secondly, this is a big-ass plane. Its nick-name was "Whale", because it was the biggest plane to ever be flown off a carrier flight deck. If one of them got pulled out of retirement, rehabilitated, and put onto a carrier, someone would have noticed. I mean, we're talking *big*. The damned thing weighs 38,000 pounds *without* fuel and bombs, it's twice the size of any current jet that flies off a carrier deck, you don't hide something that big! Thirdly, flying an unmanned "drone" off the flight deck of an aircraft carrier ain't happenin', and because the A-3 has no ejection seats (and no way to retrofit any due to the cockpit design), it's unlikely that any pilot would volunteer to fly a kamakazi mission. Finally, it takes dozens of people to launch a jet plane off the deck of an aircraft carrier. You can't launch a jet plane in secret. It has to be fueled, the deck crew has to guide it to the end of the runway and hook up the catapault hooks, the operations crew has to clear a flight path... you just can't hide it, and if there was a conspiracy of this size, someone would have leaked by now.
Which brings up what Karl Rove O'Brien called the Conspiracy Theory Conspiracy. That is, that whack conspiracy theories of this sort are generated as "black ops" by U.S. intelligence agencies (See: COINTELPRO) in order to hide the fact that there are real conspiracies out there. 25% of the world's prisoners are in the United States, despite the U.S. having only 5% of the world's population. We are swiftly becoming a prison state where an astounding 10% of adult males of some minority groups are imprisoned in the American Gulag, a vast decentralized system of county jails, state prisons, and federal penitentaries that is the fastest-growing industry in America today. There are currently eight million people caught in the claws of the American Gulag. How did this happen? Who is responsible for this? Alas, if I start speculating, I am merely putting forward a "conspiracy theory" -- which, thanks to the Conspiracy Theory Conspiracy, means it's automatically discredited.
-- Badtux the Conspiracy Penguin