Though hardly a new phenomenon, terrorism has assumed greater political saliency since the events of 9/11. Unfortunately, this greater saliency has not resulted in more effective strategies to counter the terrorist threat, the nature of which is often poorly understood. This essay describes terrorism as a method, then develops a model of what terrorist organizations look like and how they function, focusing on their evolution from hierarchical insurgent groups of the pre 9/11 era to network-like structures of today, such as al-Qaeda.
