As much as possible, the belief that al-Qaeda and Saddam Hussein were partners in the planning and execution of the events of 9/11 has to be suppressed. Or at least in the eyes of those who want to escape blame for their inattention to duty in the critical years between the end of the first Gulf War and the onset of the invasion of Iraq in 2003.
Even the “Shan” (previously known as the “Former Occupant of the Oval Office, 1993-2001”) was certain that al-Qaeda was the driving force behind the planning and execution of the attack on the World Trade Center and related attacks on the Pentagon and what was presumed to be an attack on the White House or Capitol itself. But al-Qaeda did not exist in a vacuum, and Afghanistan simply did not have the sophisticated infrastructure for training in methods of overpowering and taking down the crew of a jetliner. Saddam had just such a facility, at Salman Pak. This HAD to be coordination at a very high level.
Occam’s Razor. The simpler explanation is very likely the more nearly correct one. Making up all kinds of stories, that the destruction of the World Trade Center and the Pentagon were somehow the work of a cabal within the Federal government, gets so far-fetched as to be the source of shaking one’s head.
Both Osama bin Ladin and Saddam Hussein had enough dislike for America, that easily overcame any distaste they had for each other. Iraq and al-Qaeda were allies BEFORE the invasion in 2003.
Further, regardless of whether or not Al Qaeda was allied with Iraq before 2003, and regardless of whether it was right for us to go in, if Al Qaeda are with the troublemakers there now, that's a good reason to stay.