OK, I'll bite. Conspiracy theories can be like jigsaw puzzles where you can see the picture but the pieces don't fit together.

One good reason why Dubya didn't know - what if he was caught out? Some people would have found it a delicious irony that he was executed for treason - others would have been happy having him tried for criminal negligence.

Jack, you ever see the photo of him being told of the attacks? That is not the face of a man who knew.

My personal theory? No one knew, except al Qaeda. Rumsfield was too busy masturbating over Star Wars, and no one even gave it serious consideration: the al Qaeda pilots were seasoned and deranged fanatics determined to kill as many innocent civilians as they could, who would rather give their lives than give up a secret. The oil companies have seen a big opportunity - they haven't engineered something like this - what if someone leaked it? (read "When Good Companies do Bad things" by Schwartz and Gibb) The CIA had no decent field operatives inside of Afghanistan since their funding dried up, so they knew jack shit about anything (and someone should be sacked for that) and the FBI are cops, not MI5 (domestic espionage - Americans don't like their government spying on them).

You are offering a picture where the pieces don't fit. I'll give you Cuba, and I might even barely give you Pearl Harbour, but I won't give you the WTC on the basis of insupportable conjecture.