I'd say that one of the easiest ways to stop terrorism are to stop people joining and stop people funding it.

How to stop joining? Let's get people in the society, show that we care. No matter religion (I've heard of people who don't believe in Islam but want to join Isis for example), those people who join don't have a thing in their lives, they're sad, lonely they don't have job or place to study. The organization gives them what they want, a community, friends and feeling that they're part of something. Oh yeah and when they join much likely they have to kill people and themselves, but of course that's not put in words that way, it's more likely "you'll be a hero". They have there ordinary men, women and even children. I don't think most of them even know what they're doing.

Second thing is to stop funding as I mentioned earlier. Biggest money come from oil. Isis has oil. For example I find it very much likely that USA is buying oil from terrorists (I mean, it's possible to hide if you really want to) so if we stop using oil, terrorists will get less money. It won't hurt countries in Middle East that much since only few people get their living from oil money and they're already getting prepared for the time when there's no oil. It would also make less conflicts when people don't have to fight and global warming would slow down a bit. Also they got a lot of sun there so how about solar energy? That would be solution for many problems. Let's not use oil anymore. It starts with people, every gallon you don't use might save lives.