[bcook]

Thanks for the link (I love gwern). Terrorist organizations are always evolving though. For example, the ongoing PR campaign by ISIS. The PR is creating terrorists but there is never a singular attack. I would say the PR campaign is successful, but many people are unaware of it, compared to 9/11.

My point is, terrorism is not exclusively a single, concentrated moment of terror. Some terrorist plots are more subtle and long-term.