What I don't understand about this perspective is that these self-radicalized people are taking their inspiration and, in some cases, training from ISIS. So, is the root of the ideology coming from the Middle East / North Africa or isn't generating in isolated pockets in Europe? The US seems to think it's coming from the ME and seems to have the impression that wiping out the core group (Al Qaida 10 years ago, now ISIS) is going to eradicate the ideas. Seems like the tactics of drone strikes and lobbing bombs are instead dispersing the ideas and while ISIS's head quarters is weaker, the pedestrians in England and France (etc.) are less safe.
I personally think this has to be about eradicating a set of bad ideas that emerged from a perverted reading of the Koran. Battling ideas with weapons is extremely difficult because I think that requires ultimately killing nearly everyone that adheres to the bad ideas, some sort of full scale invasion like we had to do to "eradicate" extreme nationalism in Europe in the late 1940's. The west needs to develop a strategy for eradicating these bad ideas that doesn't involve reciprocating violence. Some research has shown that violence spreads similarly to contagious diseases (e.g.,
https://www.ted.com/talks/gary_slutkin_let_s_treat_violence_like_a_contagious_disease), perhaps reinventing our models on the spread of radical ideas and violence would be a good place to start in rethinking our policies on how to counteract Islamic terrorism, and any other form of terrorism.