Radicalization during adolescence: What have we learned from the last 4 years of empirical research?

Adolescent radicalisation is a relatively recent phenomenon that has become a public health concern since the 2015 attacks and the advent of the Islamist State. In this article, we propose a perspective based on the study of the literature and our own research and experience to delineate the main risk factors and possible trajectories that can lead to adolescent radicalisation. To do so, we review the early definitions of radicalization from criminological studies on terrorism; we summarize the literature by distinguishing between surveys on sympathy for radicalization ideas and behaviors, sociological surveys, longitudinal sample studies, and case series from specialized consultations or forensic expertise. This set of data shows the diversity of trajectories and how the phenomenon of radicalization during adolescence is infiltrated by the adolescent questioning with its issues of individuation and sexuality. However, three cases seem to emerge. The first and rarest is associated with an acute psychiatric breakdown. The second concerns youths with psychological and developmental issues (individuation, depressive fragility, identity questioning) and who initially resort almost exclusively to social networks. This case is more common among converts to Islam and family issues are very frequent, but it is more sensitive to educational and psychological interventions. Finally, the latter, more frequently associated with an assumed violent radicalization, is more often part of a local or neighborhood environment with individuals who are particularly permeable to the outer control in a form of relational clinging or who have already been involved in religious radicalism for a longer period of time. In terms of prevention, it seems legitimate to take into account all these factors and trajectories, and to consider, as in the case of suicidal behavior, different levels of radicalisation: sympathy, ideas without or with sectarian or violent commitments, intentionality and acting out. This gradation also has the advantage of being applicable to other expressions of radicalization (extreme right-wing movements, Black Blocs, ecological militancy through direct action) that are also emerging in our increasingly polarized Western societies.