(This is based largely upon reading. I don't think I've ever met a terrorist.)
Some of you might be surprised, but terrorists are not usually mentally unbalanced. In fact, they tend to be well-educated and relatively normal people. That's why they are so hard to find.
It starts with someone who says, "The way it's done doesn't make sense. It should be done this way." Perhaps you've said that? I know I have. Anyone who gets an education probably has said that at some point.
Anyone who says that is a potential terrorist.
Give me a few thousand dollars and the power to break inertia, and I will change the world forever - for the better. There's no secrets involved. I could just back existing products, products that people don't buy but are better than the ones people do buy. That's the key, you see: not money, not genius, but inertia. Inertia is the reason for every stupid, short-sighted decision or lack of decision. A fear of change, a level of comfort with the way things are, confusion as to which path is better.
If you've ever said "they should do it this way," that's always been followed by, "but they won't." Always. Because they won't. They never do.
The next step is to convince that person that a certain action will make people listen to them. For example, "Get a livejournal, people will listen to you!" or "Write a song about it, and people will listen to you!"
Or, more sinister, "Kill people, and people will listen to you."
Obviously, that last leap is not a common leap to make. But it can be made in certain circumstances.
The pattern is relatively clear. It happens when someone (A) feels they know how the world could be improved and (B) can't improve their world and (C) finds no other solace.
For isolated terrorists - people like the Unabomber, people like the children who shoot guns in schools - the problem is primarily in a lack of solace. They have nothing to ground them in a comfortable reality. They are filled with disgust at the way things work and despair at their ability to change those workings. Without anything to take that edge off, they resort to methods of communication which will "insure they are heard."
In lesser situations, this might be dressing in gothy clothes. Or posting bad poetry to a livejournal. I'm not saying these sorts of people are terrorist risks. These sorts of people are probably NOT terrorist risks, because their method is interactive. It actually does communicate, if poorly. Therefore, they are getting feedback, and changing their world. That means they are unlikely to become terrorists.
No, the isolated terrorists seem to largely be the result of NOT finding an interactive method of communication. Unable to communicate for whatever reason - be it social, physical, or mental - they resort to extreme methods. This can be shooting, it can be suicide, it can merely be attempted suicide or being a total bastard.
The problem is that they see a better world - often, simply the one everyone else is living in - and can't reach it.
These scattered events might be able to be controlled by controlling the environment. But I'm here to talk about terrorist GROUPS.
Most religions provide a level of solace to their worshippers, distracting them from the evil idiocy of the rest of the world. However, some sub-religions fan the fires.
These groups highlight an idealistic view of the world, highlight the fact that nobody will move towards it on their own, and then push. And push. And push. The people involved could be making a solid living. They could have families. They could easily have a level of solace. Most do, because people who have no solace generally are so anti-social that they never get the option to join a group of people. But even solace isn't enough - the vision of this world-to-be outstrips it. Think of it as scales: your solace weighs a certain amount. If they put more than that amount on the other side, you tip.
The only remaining step is to provide a means of dealing with the situation.
Some of these sub-religions offer solace - give them your money, live in their confines, and seperate yourself from the world.
Some of these sub-religions offer to let you change the world. Often, though violence.
And a terrorist organization is born.
Does it have to be religious? No, but people will categorize it as religious even if it is not. The unbelievable crimes committed during WWII were not caused by a religion, per se, but by a vision of a world to be acheived. A vision brought on by Hitler and his team.
In theory, anything could be brought to this level. Even Linux evangelists, even Trekkies. The difficulty is getting a chain reaction going where each act of violence causes further strength in your position.
This can only happen in a few situations. It can't happen in America as it is. It happened in the America of the past: the KKK was a terrorist organization. They became SO popular that they didn't actually have to do much terrorizing. Just existing was enough. Superman eventually brought them to their knees - no joke, and a very interesting story - but until then, they were where every bigotted male went.
But now, we have no generally accepted enemy within striking distance.
That's not true of many countries. When you have groups who hate each other, violence against each other is very popular. An act of violence will get recruits.
The enemy used to be other natives, other religions. Now it's the interfering soldiers from the west.
How can you break this cycle?
Exterminating them might work. You'd have to act pretty fast, killing most of them within a few weeks, so that they couldn't springboard off your attacks into a new popularity. That's not, however, a generally acceptable method. Moreover, I'm not at all sure it's possible.
Improving their world might work, but it would take quite a long time due to its indirect applicability to their view of the world. The higher level of solace is good, because it diminishes their number of willing recruits.
Diminishing their worldview would probably work: a massive but relatively subtle disinformation campaign which mocks their vision of the future. They'll expend a lot of energy trying to kill you, but once that's done, they'll be no more recruits. However, this is very much a religion-killer action, so it would draw a lot of bad press.
Improving their ability to change the world would just make them worse. Ask North Korea. Diminishing that same ability would also make them worse, because violence would then become their only option.
I think I would choose the disinformation campaign. Seed a derision for terrorism and, if possible, the religion which spawned it. There will be violence as they lash out at you, but so long as you do not falter and persist in your seeding, you should be able to turn public opinion around in a matter of a decade, perhaps.
Well, thanks for reading. It's all just derived from books. I claim no real experience in the matter.