That may or may not be the case - but neither one of us has the way of knowing it. We can just speculate - yours is as good as mine.
I think one can think of other possible explanations of the Iraq debacle - for example, a big blunder resulting from the lack of leadership in Washington. It is possible that a small group of hawks saw an opportunity to go with their agenda, and Bush went along instead offering leadership. Similar situation took place during the Cuban Missile Crisis - hawkish factions of the military wanted to invade, but Kennedy did not want to take the risk and resisted, preferring the diplomatic course. The history proved him right - he won in the long run, and if the US attacked, the Russians would have almost certainly used the tactical nukes which they already had in place (which the US did not know until much later) - which would likely lead to WW 3.
But nobody knew that for sure when the decisions were being made during the Crisis. What mattered was strong leadership and the ability to resist the pressure of Drs. Strangeloves - Kennedy had it, Bush does not. Consequently, Kennedy did not screw it up, Bush did.
But as I sad, we have no way of knowing for sure, we can only speculate. Since I have little patience for determinism and omniscience, and prefer a much fuzzy, uncertain and contingent view of world affair, I have a natural taste for the second explanation.
Wojtek