LinkedIn has the Cass Sunstein article Why They Hate Us.
Social networks are often responsible for terrorism — as, for example, when terrorist leaders create groups of like-minded people, breeding a sense of rage and humiliation, which feeds on and intensifies itself. We cannot understood (sic) the roots of terrorism without understanding the phenomenon of group polarization and the importance of social networks.
This article does an excellent job of identifying and describing a problem. It introduces an idea that was novel to me. However, the article has a flaw that I find in many such books and articles that do an excellent job of identifying and clarifying important ideas. The solutions that they propose are almost always vague and difficult to imagine how to implement.
What are the lessons for policy and for law?
The simplest and most important is that if a nation aims to prevent terrorist activities, a good strategy is to prevent the rise of enclaves of like-minded people. Many of those who become involved in terrorist activities could end up doing something else with their lives. Their interest in terrorism comes, in many cases, from an identifiable set of social mechanisms (generally from particular associations). If the relevant associations can be disrupted, terrorism is far less likely to arise.
In this case, the possible implications of the solution are almost as frightening as the original problem. I am thinking of the context of the political revolution that Bernie Sanders is calling for. I do see the social dynamic described by Cass Sunstein as occurring in groups to which I belong as far as a tending toward more extremism. However, the people who are trying to thwart this political revolution are using exactly the techniques that Sunstein recommends for controlling terrorism.