Mock terrorists, rather than fear them
As Steven Levitt pointed out in “Freakonomics”, this approach worked well in embarrassing the KKK.
If you could erase the fear embedded in the citizens of the Muslim / Arab world and replace it with laughter and mockery toward both the actions and the cause of terrorists regimes, you could possibly deter those who might have been future followers of that ideology.
It would be harder to join a bunch of fools than heroes so all that is needed is the right type of publicity.
“I want to quit ISIS” lol. Read this https://www.devex.com/news/why-more-groups-are-calling-on-comedy-to-counter-violent-extremism-91155
Chuckle.
More here. its a thing.
this idea may be the one that defeats the problem in the end.