Matt tackles the question:
...the war sales pitch was deeply dishonest. No fair-minded person could possibly deny that the overall effect of the way the administration talked about Iraq was designed to get people to believe that there was a short-term threat that Saddam Hussein would transfer a nuclear weapon to al-Qaeda for use against the United States of America. It's equally clear that this was not supported by the evidence. But more to the point, it's perfectly clear that the whole pitch was made in bad faith. The administration had a different, more nuanced and more medium-term set of concerns about Iraq. It believed that preventive war was the best way to deal with those concerns. And it also believed, correctly I think, that the public would not support an action of pure "anticipatory self-defense." Thus they took bits and pieces of real intelligence plus some very flimsy stuff plus some made up stuff plus some rhetorical excess and they weaved their dishonest tapestry.
Yes: but this captures the complexity of it. I bought both parts of this argument, and feel duped about one and utopian about the other. Maybe it's better to think of the Bush administration as having acted in broad good faith, with a critical piece of bad faith at its center.
Their problem with the bad faith part was that it was subject to empirical refutation. I think they never believed it could be - there would be some remnants of WMDs, they thought, even if the scale of the effort they were describing was phony. And, boy, were they wrong. In retrospect, I think the bad faith seriously tainted the good. And, more than anything except torture, delegitimized the entire project.
And what made it even more nauseating was that no one really took full responsibility, least of all the president. The man made a joke about missing WMDs, for goodness' sake. And most neocons seems incapable of self-criticism or even much self-awareness.