"An internal Iraqi Intelligence memo that Bergen describes as "one of the most credible documents," and was first reported by the Times in 2004, suggests that a better question is: "Why did Saddam help al Qaeda?"
Because Saddam is a Sunni and Al Queada are mostly Sunni's. And they hate the Shiites.
That is not why.
The enemy of my enemy is my friend. Hatred of the US fed their relationship.
Perhaps it was because Joined Iraq and declared war on our Republic in 1998.
IIRC Operation Desert Storm ended in a truce, We were in a state of war with Saddam until Op Iraqi Freedom.