Personally, I think we may never know for sure. There are certainly people who were inside the US government that stood to gain. Then there's Israel and Saudi Arabia as well. Probably, it was a joint effort by rogue groups inside multiple intelligence agencies from the US, Israel, and Saudi Arabia.
Definitely don't buy the official story, though.
Valid comment! Thank you! Upvoted! =)
Interesting to consider GW may have known nothing about it, and his dad, and the VP, are running the show...
Most of these things are a cabal, and the insiders are very secure, about who gets the actual info.