The economic analysis of conflicts assigns a crucial role to the rebellion making process. However, the existing literature on this issue often rests on unsatisfactory micro- foundations. It tends to overemphasize two extreme forms of mobilisation, namely purely greed-driven or, alternatively, purely ideology-driven. It does not fully address the puzzles associated with the leader-followers interaction within violent organisations. The present paper is an empirical account describing how rank and file members of an ethnic militia are mobilised. The survey shows that the purely economic explanation of violent mobilisation does not hold despite the fact the militia levers its own funds. At least two other considerations are at play for members: first, the feeling of danger, the desire of protection against fuzzily identified risks (criminality, unknown future, menace from other ethnic groups etc.); second, the social proximity to militia insiders. In fact, vulnerability (either perceived or real) might be a more decisive factor in enlistment than poverty per se. Additionally, the paper suggests that the militia studied in Nigeria doesn’t fit the usual binary classification of rebel groups (predatory or ideological) as it is simultaneously an economic, social and political actor in the communities where it operates.