“Radicalization” is the title of a book published in 2014 by Farhad Khosrokhavar, a sociologist at the École des Hautes Études en Sciences Sociales (EHESS), so that we can immediately understand that his study focuses on the phenomena of political violence. The context for the book’s production is at a time when Europe is facing an unprecedented influx of its young people to the Middle East, with “some 1,500 to 2,000 Europeans believed to have joined Syria, including a few hundred french”. What is “radicalization”? This notion of “radicalization” is defined by the author as a “process by which an individual or a group adopts a violent form of…