What is the relationship of bin Laden's ideology to the rest of Islam?
and What is the relationship of bin Laden's type of "Islamist fundamentalism" to other types of religious fundamentalism?
The discussions are often shaped, unfortunately, I think, by two overblown and misplaced concerns: to not offend Muslims in general and to make sure religion in general doesn't become a culprit.
One of President Bush's primary advisors on the matter, David Forte, seems particularly intent on drawing all kinds of lines between bin Laden and religion, period. His conversation-starting article can be found here in the National Review. (Actually, the conversation was started by Andrew Sullivan in the NYTimes Magazine. Article's here. ) Subsequent responses in the pages ("on the screens?") of NRO have come from Daniel Pipes and today, , Stephen Schwartz. Here's a good summary of the dispute so far as it centers around the specific issue of the role of violence within Islam: Click here.
I don't really understand Forte's concern or cause here. Of course bin Laden's ideology is rooted in Islam and has a religious component, although it's also true that he's more akin to medieval princes setting forth under the cross of the Crusades to whom religion was a cover for looting, pillaging, adventure, and getting to build their very own castles in Palestine. But sure, it's "religious" in a way, and it's certainly "fundamentalist", too, and as such bears the qualities of all fundamentalism, whether that be Christian, Islam or anything else - selectivity.
People are often wrong about this. They define "fundamentalism" as a religious perspective that takes "everything literally" and applies all tenets of a religion to life without discrimination, sensitivity, nuance, context or mercy. That's just not what fundamentalism is - it's selective application of literal readings of one's religion. Do evangelical Christian fundamentalists apply all of what they read in the Bible literally to life? Of course not. If they did, they'd all be living in community on just what they need, celebrating eucharist every week and believing that that same eucharist was Jesus' Real Presence among them. Uh...they don't.
So very properly defining bin Laden's ideology as one that's partally rooted in Islamist fundamentalism of a certain type is correct, and saying as such doesn't cast a shadow on religion in general, or on orthodox Christianity specifically.