There are interesting parallels between the processes that lead some people to join both religious cults and terrorist groups. If you once joined a cult you will very likely recognize some of the pathway others have walked to become members of a group responsible for violent terror attacks.
If you joined a religious cult you knew that others thought you were a bit weird. Numerous accounts of those who joined terrorist organizations show that those becoming interested in an extremist group were aware their families and wider society would try to talk them out of it so they kept their interest secret from everyone except others, if any, whom they knew shared their views.
Joining either means turning one’s back on society and immersing oneself totally in an alien way of life.
Jerrold Post appears to have been the first to recognize that cult recruiting can provide a useful model of terrorist recruiting. The analogy begins by noting that individuals who join either a cult or a terrorist group are likely to be characterized as “crazy.” Both a cult and a terrorist group require a level of commitment that most people find difficult to comprehend.
McCauley, Clark; Moskalenko, Sophia (2011-02-02). Friction: How Radicalization Happens to Them and Us (Kindle Locations 1709-1711). Oxford University Press. Kindle Edition. — (My bolding and formatting in all quotations)
McCauley and Moskalenko in Friction: How Radicalization Happens to Them and Us take up this comparison.
Here we focus on recruitment to the Unification Church (UC) of the Reverend Sun Myung Moon. The UC is generally regarded as a cult, and, more important, there is an unparalleled research literature for this group. A 1965 report by Lofland and Stark titled “Becoming a World Saver” chronicled the beginnings of the UC in America, and the surprise value of the report was its emphasis on the importance of social networks in religious conversion.