And a bonus reason (my own pet theory): they wanted to demonstrate to the world the Rumsfeld Doctrine of underwhelming force--a prong in his PNAC scheme for military transformation. Rumsfeld et al. are pushing to reequip the U.S. military with very expensive, high-tech toys. Oh--and with "enduring" bases all around the world to enable "light" "mobile" "agile" "etc." military actions.

The theory, I gather, is that if our fighters have the right gizmos, we can enter a war zone with a fraction of the troop strength we used to need and still walk all over any army in the world. A force in the hundreds of thousands to take and stabilize Iraq? "Hah," says Rumsfeld, "We'll do it with half that, some contractors to cook the food etc.... oh, and don't forget our high-tech doodads."

Obviously, there are huge financial bonuses--in the form of future consulting contracts, spots on boards of directors, etc.--for Rummy and Cheney and the rest of them when they leave office. It's that classic profiteering move where you sign the Pentagon on to a bunch of new toys, establish a pipeline for the next 20+ yrs of procurement, then leave the government and conveniently find yourself involved with the suppliers of the toys you just ordered. There wont always be oil, but there will always be profitable war over what little remains. Getting rich off that (and preparing for that) is the point of "transformation."

I should note that Iraq has NOT proven the wisdom of Rumsfeld's scheme. But he's not letting that stop him. He will transform the military come hell and/or high water.