As we have seen in the cases of Serbia and Israel, collectives can be mobilised to perpetrate grave wrongs on the basis of patently ideological claims about the harms they have suffered. This article seeks a theoretical understanding of this troubling phenomenon. It does so, first, by contrasting mobilisation based on vicarious victimhood with revenge. The groups in question do not exhibit the contact with reality and clear sense of agency that are prerequisites for revenge. However, these evasions of agency and reality are not specific to group identities centred on victimhood. Second, therefore, the article considers the attractions of such an identity and how it reinforces groups’ tendencies to myth-making and irresponsibility. Among its more harmful effects, it obscures the realities of state power and forecloses meaningful accountability to those outside the group. It also sets in train a vicious circle, whereby the group discovers perverse incentives to harm others – and to harm itself. Yet these harms only reinforce the group’s self-anointed status as victim: as always done by, never doing to.