Once the conflict begins it really won't matter if Saddam uses surrogates or terrorists traceable to him. One thing he does need is to make this conflict look like a war between the U.S. and pan-Arab or Islamic forces. To that end, al-Qaeda terrorist actions made all the more dramatic by the use of WMD provided by Saddam is very plausible. If you look at Uday's (Saddam's son's) statements of late, he is trying to frame the pending conflict as one against all arabs instead of one against Saddam and his cronies. Saddam may also be considering using al-Qaeda and others to destablize Saudi Arabia or Egypt to throw the U.S. off balance and buy more time for his sorry regime.
One thing he does need is to make this conflict look like a war between the U.S. and pan-Arab or Islamic forces.
He may want this, but do the leaders of the other nations in the region want this? No.
Would they like to see us embarrassed, or hurt, or even defeated, of course. But are they going to do anything that would cause the full weight of the United States military come down on them? No.
Having said that, I will admit once military action begins events can get out of hand. I do not believe anyone knows what the final outcome (beside the death of saddam) will be.