In general, I reject the "evil genius" characterization of Bush that occasionally gets tossed into the conversation. I reject the "genius" part of it, for one thing. But I'm going to quote here from part of Salam Pax's blog that I read today in the Guardian Online (remember the Baghdad Blogger?). He talks about visiting DC and going to a political rally where Al Gore is speaking, and this is what he says that Gore was trying to get across:

"... dismissing Bush as someone who "does not have the normal, active curiosity about separating fact from myth" or as a born-again Christian who "relies on religious faith in place of logical analysis" makes him less dangerous. It makes him too easy to dismiss and underestimate...

Gore dismissed both those views as "cartoon images" and added: "I am convinced that the president's frequent departures from fact-based analysis have much more to do with rightwing political and economic ideology than the Bible. "Most of the problems president Bush has caused for this country stem not from his belief in God but from his belief in the infallibility of the rightwing Republican ideology . . . it is love of power for its own sake that is the original sin of this administration." "

In other words, not stupid or crazy, but evil. Calling him insane may have a similar effect, of trivialing how potentially dangerous he is. Something to think about, anyway.