The possibility of Iranian involvement in the attacks was a surprise to many foreign policy specialists at the time of the report, given the Bush administration's fixation on the possibility that another country—Saddam Hussein's Iraq—was tied to the 9/11 plot, a connection that was mostly rejected by the 9/11 Commission.
God almighty how long will this false charge live? The Bush administration was not fixated on the possibility that Iraq was involved in 9/11. The Bush administration did not even argue that Iraq was involved in 9/11. While I would not be shocked to find that they were involved, so far I've seen only indications of linkages between al Qaeda and Iraq in general rather than plot coordination. Indeed, when the attacks occurred, I figured there were two suspects--al Qaeda or Iraq. Iraq never rose out of the ranks in any arguments I ever heard.
What the Bush administration said repeatedly about Iraq was that in light of the 9/11 attacks we couldn't afford to risk an anti-American regime like Saddam Hussein's Iraq continuing to operate given its record, potential oil wealth, and support for terrorism. Anti-war types constantly replied to that argument with the amazingly resilient non sequitor that Saddam had nothing to do with 9/11!
Arggghhh. And it continues! Only the out-of place, twitchy interjection of "Halliburton!!!" would fully reflect the debates of 2002.