Hold on a second, you just said, in order for any two entities to work together, they must have a motivation that is mutual.... "Because the two organsations motivations aren't the same." ...I am asking you what motivation the US and Saddam had in common, and you haven't answered. You have told me what the US motivation was, but Saddam couldn't have cared less about the US oil supply, so that is not a mutual motivation. I've also asked you what the mutual motivation was between the US and Russia in WWII. I understand that getting rid of Hitler was a mutual objective, but the motivations were completely different.
You see, the point is, entities are often allied over a mutual objective because they each have some motive which benefits them, and it doesn't have to be mutual. alQaeda wants us out of the middle east so they can continue to bully that part of the world into 5th century Muhammad Law, Saddam wanted us out of the middle east so he could continue his maniacal reign of oppression on the people of Iraq. The two groups had a mutual objective, although their motivations were completely different.