Nothing so far that wouldn't compromise principles modern society lies on. If people who do these acts have a mindset that they have nothing to lose and that t

Nothing so far that wouldn't compromise principles modern society lies on. If people who do these acts have a mindset that they have nothing to lose and that their activities are righteous, then you have to think in a way that would undermine either their belief in that or put their activities at causing them more harm then their own life. KGB did something along those lines, where when soviet officials were abducted. What KGB did was effective, but it is not compatible with modern western society: http://articles.latimes.com/1986-01-07/news/mn-13892_1_soviets http://articles.latimes.com/1986-01-07/news/mn-13892_1_sovie... Could you imagine a modern country like France abducting and mutilating and executing all of relatives of attackers? I cannot. I can imagine Russia doing so, or even Mossad. Not France. Personally, I do not think either way is a way forward. I'm jus answering your question - what can we do? There were several approaches, of which KGB's one was proven to be effective.