Good article - but:
"...The Manchester Arena bomber may be an anomaly in many ways,.."

I will suggest he is not an anomaly but representative of Islamic culture.

My experience as a teen age immigrant - your family's culture emigrates with you and all immigrants seek to live in association and/or near others of similar experience. Thus we have " Little Italy ", " China Town ", Germans, Ukrainians, Swedes ... living together and trying to maintain their culture, language, food .... religion, staying within their confort zone. 

Religion does play a significant part ... and it is a question of what the religion values. Eastern beliefs tend to be philosophical, less theocratic. Christianity separates Church and State, whereas Islam is specific about the state and Islam being one, under Sharia law. There are of course many sectarian variations - but Islam is an unstable mix of petro-dollars,  madrassa education and Wahabbism by way of an extreme example, 

What could possibly go wrong  !