The Difference Between Howard and Bush?
Australian PM John Howard pretends not to know anything, or makes sure he isn't told things, or ensures that there is no evidence proving that he was told things.
Bush just doesn't know things - because Cheney, Rumsfeld and the other gangsters don't tell him. Or else, confronted by facts, he makes a faith-based decision to ignore them.
I reckon the Lie Detector Test is a good idea - all politicians should be permanently hooked up to one, particularly when debating policies or making TV appearances.