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This article talks about how “network theory” can be used to find terrorists. People studying networks have found “surprising commonalities” between airline routes, people’s interactions at cocktail parties, and crickets’ synchronization of their chirps. These people study networks to have an easier time figuring out non-trivial patterns. New algorithms are being developed and used in exposing these patterns in large chunks of data, like examining e-mail traffic of 43,000 people at
Columbia by Duncan Watts. Stanley Milgram found that most pairs of Americans can be connected by six different people, called the “degrees of separation”. In another mapping, Valdis Krebs decided to map the 9/11 hijackers by starting with two of the plotters and produced a chart of the interconnections within the group. All of the 19 hijackers were tied to one another by just a few links, while many of them converged on the leader, Mohamed Atta. Interestingly, before 9/11 an Army project attempted to map Al Qaeda by “identifying linkages and patterns in large volumes of data,” which may have succeeded in identifying Atta – but he was among a lot of other possible suspects. The problem is that most people are connected to hundreds of thousands of people by only three degrees of separation – leading to many false positives. In analyzing these gigantic networks, some look for network hubs – like Google or Newark airport that have many more links than the average node. However, it cannot be easily done. Similarly the “strength of weak ties” in network theory can be also the key to analyzing these networks. Even if the hubs can be identifying in the terrorist groups, the story is not complete. Like Watts said, “If you shoot the C.E.O., they’ll hire another one.”

This article mentioned a lot of things that we learned in networks. A lot of phenomena are mapped by making people “nodes” while the “edges” represent the relationships and interactions between the nodes. It mentioned the Duncan Watts paper, the “degrees of separation” from the Tipping Point, and the “strength of weak ties.” Identifying a terrorist network is not as simple as analyzing the e-mail traffic at Columbia University. The answers could be in identifying hubs or in the “weak ties.” With so much volume of information coming in, even if it was possible to reliably identify the hubs – these networks are so large and robust that eliminating the hubs would hardly affect them. In addition, it is harder to create a network of terrorists than a network of college students who send e-mail, because the members of university are known while the terrorists are not. While the patterns of terrorists are only beginning to be figured out, these network theory concepts should be helpful in creating a map of the terrorists’ network.