Many years ago I read something that made a lot of sense to me: it was a “circles” theory of combatting terrorism.
In the innermost circle are the active terrorists, people who are in the movement and firmly, clearly committed to inflicting violence on civilians. There’s no real answer to these people other than police or military action.
In the next-most circle are the fence-sitters. These are people who are prime targets for recruitment by terrorists: they believe that someone (Israel, America, The Jews, The Blacks) have done them wrong, and they’re trying to decide what to do about it. For these folk, a clear carrot-and-stick approach might be best. Convince them that moving into the terrorist circle will be bad for them and their goals, and that moving out of the circle will leave them with options for fulfilling their goals.
In the next-most circle are potential recruits. These are people who are suffering, but haven’t yet decided that there’s an enemy responsible for their suffering. These people need support. Outreach to them in terms of community, food, medicine, jobs, etc. can be extremely effective at turning them away from recruitment. Conversely, terrorist groups love to offer these things as a recruitment tool: if you don’t get there first, the terrorists will.
Outside of the potential recruits is the general public. This group needs propaganda, in its most benign form: this group need constant, persuasive evidence that the terrorists aren’t accomplishing anything for the people, whereas non-terrorists are.
Too often, people focus only on the active terrorists. But a focus only on them, without also paying attention to the concentric rings, means there’ll constantly be new recruits, replacing any terrorists who are captured or killed.