As a side note about the manner in which the war was funded. That is really the best way to fund wars since you are able to get an actual number of how much it is really costing. To put money up front for it is simply a guess, and more than likely more will have to be added later.
Rob that couldn't be more of a trick if it had a magicians cape wrapped around it!
It's obviously much better that the American people at least get some idea of what a particular budget cost a conflict will be than to get no idea at all. And if you never budget for it and it just keeps evolving as however you want it to then that's no more accurate at all.
This was just another Bush tactic to push the invasion and following occupation. People don't like the costs of wars. He simply didn't want that costs constantly bashing him in the face in the budget everyday.