This paper will explore young people’s disposition and vulnerability to violent extremism and radicalisation based on the analysis of a cross-country online survey carried out within the Horizon 2020 Participation project in 2021–2022. The survey was carried out among young students in six European countries (the UK, Poland, Greece, Belgium, Romania, and Italy). Our analysis explores this further by looking at young people’s behaviour, attitudes, and socio-economic background to understand specific vulnerabilities to violent extremism. The paper builds on the post-organisational and post-ideological expressions of extremism literature and argues that online behaviour, attitudes towards gender equality, belief in conspiracy theories, and being from a marginalised group are areas that indicate vulnerabilities and might be potential pathways towards violent extremism. Research results confirm that the support for violent extremism among young Europeans is linked to a social context characterised by atomisation, isolation, anomie, and a sense of existential marginality—conditions inherited from adult society during a crucial phase of socialisation. In this context, supporting political violence is part of an eccentric process of subjectivation. Therefore, preventing and understanding radicalisation requires an analysis of living conditions, social stratification dynamics, and the significance attributed to the construction of social and individual identity.