Violence is a force for creating integrities as well as one that violates, pollutes and destroys already existing entities. In this paper I address the role of what Ariella Azoulay terms the ‘political imagination’ in constituting social aggregates committed to the defence of a community itself brought into being by the imagining of a force dedicated to its destruction. Such a group’s perception of what Laclau and Mouffe call an ‘antagonism’ spurs it to mark out and defend its boundaries with violence – a violence often manifested aggressively (pre-emptively). Collective perceptions of an other’s antagonism are often overdetermined, either by historical memory or political manipulation, and it is often the case that an enemy is sited and a programme of ‘defensive’ violence inaugurated without any ‘real’ justification. Here I demonstrate, using events drawn from the formation of the State of Israel and the collapse of what is now ‘Former Yugoslavia’, that it is in designating an other against which destructive violence must be mobilized that an entity realizes – through the negation of that it would negate – what it is it fights to defend.