Nigel Biggar considers the impact of just war thinking over time – including a recent revival of interest.
Yes, I think just war thinking over time has had an impact on the way people think about war. So here’s one example: the justifications for the early medieval Crusades were not made in terms of just war thinking. They were made in terms of appeals to authority – the Pope, in the name of God, calls for a crusade. In fact, just war thinking came into being as an alternative to that rather authoritarian justification, when canon lawyers in the 13th century began to articulate rational norms to govern decisions. So that by the 14th and 15th centuries, even when popes start to call for the use of armed force, they will then start to think in terms of the just war criteria. So certainly in that period, I think you can see the way in which just war thinking has functioned to subject going to war to a set of criteria that constrain it.
Since about the 1990s, just war thinking has enjoyed something of a revival. The reason for that, I think, is that up until the end of the Cold War, because of our preoccupation with the threat of escalation to full nuclear exchange, the occasions when we would go to war directly were quite constrained. We would often, in the West, we’d fight proxy wars – other people would fight our wars and we’d arm them. But we, because of the dangers of escalation to full nuclear exchange with the USSR, we were very cautious about interventions. We didn’t intervene in Hungary in ’56, nor in Czechoslovakia in ’68 – in spite of the fact that the Hungarians and Czechs called for the West to intervene.
But since the end of the Cold War and the dismantling of the USSR, the possibility of intervening – let’s say, for the sake of argument, for noble purposes – has seemed to be less risky, and therefore we’ve done more of it. And I think therefore … you know, we intervened in Bosnia in the mid-1990s; we didn’t intervene in Rwanda, which was very controversial; we intervened in Kosovo in ’99. There was Iraq in ’91 and Iraq again in 2003. So all sorts of interventions that haven’t obviously risked nuclear war. And so we’ve been faced over the last 20 years with multiple occasions when we’ve had to ask these questions, and I take it that’s the reason that just war theory has been revived. Although, to be fair, elements of it were incorporated into international law in the laws of war – so treatment of prisoners and not targeting civilians, that was already preserved there. But it has flourished in the last 20 years.