I guess you support the Inquisition that went along with the extermination of the Cathars.
Of course, it took more than 100 years after Arnaud Amalric uttered Caedite eos. Novit enim Dominus qui sunt eius for them to hunt down and kill (burn) the last person who didn't believe what they wanted him to believe.
Effective, if not exactly efficient, timely, or moral.
Unfortunately, at the end of the day you have to fight the enemy on THEIR terms.
For an example a little closer to home in both geography and time, look into the USA, 1919, and the so called “anarchist summer”. People were blowing things up, blowing themselves up* - and yet it all ended. And it wasn't because we sat down and talked with anybody, or we tried to understand them, etc. Picking up the family of a dead anarchist, putting them on a boat, dumping them into a foreign country and saying, "stay the F out" was not timely or moral - but it damm sure worked!
*Eleanor and Franklin Roosevelt (then Secretary of the Navy and pre polio) spent an evening picking glass out of the floor of their front room after an anarchist blew himself up across the street in front of the home of the Chief Justice of the Supreme Court.