This commentary engages with the alternative claims on (1) the causes of radicalisation into violent extremism, (2) the motives behind radicalisation, and (3) deradicalisation as a “religious question” in Muslim-majority and Muslim-minority contexts. The commentary distinguishes Islamist radicalisation from that of the “right” and the “left”, for mainstream Islamism and Jihadism do not represent a couple between moderates and radicals. Connectedly, Roy also critically engages with the explanations of radicalisation based on social movements, political protests, or socioeconomic problems. Finally, the commentary questions how deradicalisation efforts have been centred on the religious question and how this religious question has been handled by governments in Muslim-majority and Muslim-minority contexts. Having identified a series of crucial differences between these two contexts, Roy concludes that the similarity is in that “good Islam” is built from an authoritarian and vertical approach in both Europe and the Muslim world.