ABSTRACTThe Irish Republican Army (IRA) sometimes claim that their violent actions are sanctioned by traditional just war doctrine. To what extent is this true? To answer this question it is necessary to have a clear grasp of the principles of just war and of the situation in Northern Ireland to which they are to be applied. This is done in the first sections, and it is then argued that just war sanctions some kinds of violence in Northern Ireland but only those of direct self‐defence. Violence outside the borders of Northern Ireland or for the sake of Irish Unity is not justifiable. Consequently the IRA must be viewed, in terms of just war theory at any rate, as in principle illegitimate, even though some of their actions are defensible. Finally it is suggested that non‐violence, after the pattern of Gandhi, while not required by justice might nevertheless be prefera