While the good intentions of that mission are beyond reproach, the emerging science of deradicalization is not. Koehler is upfront about how little evidence supports the notion that programs like his can weaken extremist movements: He admits, for example, that despite years of deradicalization efforts in Germany and plenty of individual success stories, the number of hardcore neo-Nazis in the nation has remained static.
Though Koehler’s research has revealed a great deal about how to guide people away from poisonous ideologies, that guidance requires such huge amounts of time and money that it can only have a limited impact. And since the science of deradicalization is so new, we don’t yet have a clear sense of what factors might cause the “graduates” of programs to backslide; in a world in which extremist propaganda and recruiters are always just a broadband connection away, re-radicalization is a constant threat.
https://www.wired.com/2016/11/u-s-judge-may-sentence-wannabe-terrorists-deradicalization/
I say throw the book at them and let them rot in prison. ISIS fanboys can't be saved.