I went to an interesting lecture last night by ordained Baptist Minister and Religion Professor Charles Kimball. He has written a book entitled "When Religion becomes Evil", and the lecture was based on it.
I thought it was very powerful, and a found it to be a guide to avoid the pitfalls of radicalism, no matter what your faith.
Here is an excerpt:
"Whatever religious people may say about their love of God or the mandates of their religion, when their behavior toward others is violent and destructive, when it causes suffering among their neighbors, you can be sure the religion has been corrupted and reform is desperately needed."