They've tortured people. They've set up whole secret camps to hold people for torture. Well, not-so-secret, really. We found out about it within a few months (on VIDEO yet!)
They wrote top-level whitehouse memos giving legal justifications for this behavior. It didn't take too long before the memos found their way into the NY Times.
They've "rendered" people over secretly to other governments for torture. We already have the serial number and pictures of the Gulfstream corporate jet they used to do it(!)
We know they even wanted to invade Iraq from their first days in power, courtesy ex-Treasury Secretary Paul O'Neill, and leaked memos he showed the world on 60 Minutes.
So, I'm supposed to believe that this gang of brutal, ignoramus shitheads, who weren't able to cover up their tracks in the commission of all these felonies and war crimes, were nevertheless able to "orchestrate" the most complicated possible scheme for staging a "terrorist attack" that would give them a casus belli for their preexisting plans, yet none of the hundreds of confederates they would have had to rely on to pull it off has come forward yet with a single memo? Not bloody likely.
Isn't it a lot more likely that, at most, they may have known something was in the works, but didn't raise a finger to stop it -- perhaps because they thought it would serve their interests? Now THAT'S a case that you can readily make. There's voluminous evidence to support THAT, starting with the revelations of FBI whistleblowers like Sibel Edmonds and Colleen Rowley testifying before Congress. But to argue that they "planned" it, "gave the order," "vectored the planes in," really, and were able to get away with it without more smoking-gun evidence of their crimes being leaked by their own confederates, that just really defies credulity. I'm at a loss to understand the appeal of such theories to rational people, other than as some form of personal emotional catharsis