I am emphasising and emphasising, and emphasising over again: following what has been happening in Spain is important to understand *one* of the evolution pathways of radical Islam in Europe. Unfortunately most of the relevant material is in Spanish. Googling I found this. I cannot vouch for the source, but the information contained in the article conforms with my general understanding. One or two extra points:
I had missed the fact Castells appeared before the 11M commission. I think it important that network theorists are involved in strategic thinking. I think the idea that there are simply a fixed quantity of terrorists to be eliminated is absurd, and those who argue this kind of view probably commit themselves to something like the ‘lump of labour‘ fallacy.
Secondly illegal immigration is a really important issue. This phenomenon probably explains this sentence in the link: “The apparent ease with which foreign jihadists motivated Spanish Muslims to radicalize their religious beliefs and recruit them for suicide operations in Iraq illustrates a demographic and ideological shift among Spanish Muslims”.
Following this up, illegal immigration is the perfect cover for such activities as those who are in this situation have almost minimal contact with the value system of the ‘host’ society, and may experience many of its less desireable features. The Italian authorities seem to be taking this possibility seriously.