This rings true. But isnt the situation a bit different in some places? for example, in Pakistan or Afghanistan, the terrorism is not just to invite a backlash. It can have very immediate tactical objectives (for example, it has been reported that at least one attack in Karachi was meant to tell the Navy to back off from torturing XYZ terrorists who were in custody). And in a sense there IS a balance of power. The state backs off from certain options because it is scared of being effectively counter-attacked.
i.e. in that part of the world the terrorists are a real force, looking forward to capturing territory and running the place, and they able to pick targets with specific tactical objectives in mind, not just as a random throw of dice.
No?