I have been fascinated by counter-terrorism as one of the most intellectually stimulating topics. Somebody referred to it as the mother of all systems problems. That may well be true, for one has to take in to account complexities of geo-politics, psychology, social networks, history and culture, and technology among many other aspects.
The entire issue is so complex that I have a hard time to start picking
up different threads. My lense at looking at counterterrorism has been
mainly geopolitical, and while I find that immensely helpful in
understanding terrorism, it is hardly enough to explore the entire
gamut of counterterrorism.
I would start with Thomas P. M. Barnett's Pentagon's New Map. Watch Barnett's presentation on C-Span if you don't have time to read the book. The Counterterrorism blog provides a group commentary on different aspects of counterterrorism. Most of this analysis is US centric. John Robb at Global Guerrillas has some great analysis on possible disruptions, as well as a few theoretical frameworks for analysis which can be extended in different directions.
A while ago Frontline had two great documentaries (You know it was coming) titled Al-Queda's New Front and Cyber War. The first documentary looked at Al Queda's spread in Europe in the wake of March 2004 bombings in Madrid. The second explores the vulnarabilities of cyberspace from a terrorist attack.
I am also slightly confused about where strategic defense ends and counter-terrorism begins. Obviously, the boundaries are not clearly demarketed. Any thoughts?