To understand the revolution, my research team has conducted dozens of structured interviews and behavioural experiments with youth in Paris, London and Barcelona, as well as with captured ISIS fighters in Iraq and members of Jabhat al-Nusra (Al-Qaeda’s affiliate in Syria). We also focused on youth from distressed neighbourhoods previously associated with violence or jihadi support – for example, the Paris suburbs of Clichy-sous-Bois and Épinay-sur-Seine, the Moroccan neighbourhoods of Sidi Moumen in Casablanca and Jamaa Mezuak in Tetuán.