A FP article that challenges the traditional narrative to explain radicalisation:http://foreignpolicy.com/2016/04/13/...adicalization/

Here is one passage:
...perhaps the more realistic — and in some ways more unsettling — scenario is that the Abdeslam brothers drifted in and out of jihadi activism and that this owed more to who they knew and how they lived than anything they believed.....

Later (CVE uses) the transformational view of radicalization: Implicit in their language and rhetoric is the idea that terrorism is the end stage of a process in which people come to adopt an extremist worldview that justifies violence.