From a reader:

I think you’ve probably nailed it pretty close. Both sides in most
political debates are generally extremely quick to attribute the worst possible motives to their opponents when, all too often, it’s more likely a combination of wounded egos and failing to really listen to what someone is saying….
Regarding Clarke, most charitably, as you say, because of his frustration over past dismissals by the Clinton administration of his proposals, he misinterpreted President Bush’s understandable concern to be absolutely sure that Iraq hadn’t been behind the WTC disaster. The thing that puts the lie to Clarke’s interpretation, more than anything, is that fact that in short order Bush ordered the bombing of al Qai’da camps in Afghanistan — not Iraq!