If “the fight against radicalization" has emerged in recent years as anew major axis of terrorism prevention policies at national andsupranational levels, it underpins a serious conceptual flaw. This newimperative is far from having a clear meaning in the language of theactors, even though the fight against radicalization is likely toproduce significant legal consequences. Beyond the confusion that reignsin the use of the word "radicalization", the upheavals induced by theshift from the fight against terrorism to the fight againstradicalization reveal a need for further legal development. The proposedresearch is guided by a central thread aiming to clarify what is atstake behind this semantic shift.Conceptual clarification is first undertaken through the study ofdiscourses on "radicalization" within European, Belgian and French legalorders. The investigation covers not only the descriptive statements onradicalization as such, but also the prescriptive statements on themeans mobilized to prevent and fight against this phenomenon. Theapproach through discursive deconstruction aims to clarify the legalimplications of the notion of “radicalization” without masking theconfusions which it carries. Lessons learned from this first steprequire further elucidation both at the discursive and pragmatic level.The legal means in the fight against radicalization will be examined inthe light of the concrete application of certain European instruments innational law. Several legal changes that occurred during the transitionfrom the fight against terrorism to the fight against radicalizationwill also be highlighted. By examining the legal challenges posed by thefight against radicalization in the light of the interactions betweenthe European, Belgian and French legal orders, the project intends toenrich juridical reflection on a topic that is still relatively recentin legal scrutiny. ; Alors que « la lutte contre la radicalisation » s’est imposée depuis quelques années comme nouvel axe majeur des politiques de prévention du ...