Extremists often derive their inspiration from literal interpretations of texts that should rightly be read not as Associated Press reports from the ancient world, but as theological and literary enterprises requiring independent intellectual assessment.
We have to understand how the extremists got the way they are. Without that kind of understanding, we'd never really get to know them. I put in nothing about their childhoods. But what I have put in is stuff about the weird symbiotic relationship between us and them.
Undoubtedly, there are members of the former regime that are cooperating in some fashion and then there are extremists that are within Iraq that are cooperating with them.