Briefly: Perhaps it's true that the invasion of iraq is responisble -in the narrow meaning of the term- for much of what's happening now in the middle east, but that doesn't mean the president is getting what he wanted. The idiot shot up a hornets nest and now he's trying to control the swarm.
In the best case scenario, Israel will soon be surrounded by nations with representative govenments, but the whole logic of the Israeli right is that the sand niggers are barbarians.

From a realist (nationalist) perspective there's no doubt the Bush's war was a mistake for the US: it's done nothing but speed up the decline of American power. Of course if all the administration wanted were democratic change, it could all have come about with less violence; but they wanted control, and they won't get it.