Nigel Biggar outlines six questions to ask before going to war, and two more when engaged in one.
There have been two categories developed. The first set of criteria deals with the question of, shall we go to war or not? So before you go to war, is this a good idea? And there are about five or six criteria covering that. Then once we’ve started war, there are two criteria that govern the conduct of war.
When we think of whether to go to war, the first thing we think about is whether there is just cause. And that would be some kind of grave injustice that needs rectifying. Then we ask ourselves, well, there’s just cause, but it could be that someone is beating you up and you want rescue, so I decide to rescue you – but actually, I’m not rescuing you because I care about you, I’m rescuing you because I want the territory you’re sitting on. In other words, just cause ain’t enough, you’ve also got to have right intention. So in intervening, am I intending to rectify the injustice?
Then because war is a really hazardous and destructive business, you don’t want to do it unless you really, really have to. And if you can find peaceful means of resolving the conflict, you should do it. Therefore, it should always be a last resort, all other reasonable means of resolving the conflict having been exhausted.
You ought to have legitimate authority as well, because you can’t have anybody just declaring war. Otherwise, there’d be anarchy. So somebody that is responsible for the public good has to be the body that makes war and makes peace.
The fifth one would be the prospect of success – the idea here being that, war being a destructive and costly business, you don’t want to do it unless there’s some prospect of actually winning it. Although, in my own view, that’s a bit controversial because sometimes, if the enemy is really, really bad, then that warrants taking greater risks. So the example would be Britain in May 1940 with our army crushed in Northern France, and some people saying we should make peace with Hitler. You could say the prospects of success weren’t great then, but looking back we’re rather proud that we took the risk.
The two criteria, once you are engaged in a war, are proportionality and discrimination. And in fact, I should have said proportionality also applies when you are thinking about going to war; that’s to say, in some sense, is going to war proportionate? But once you are involved in a war, one has to ask the question, is this military action proportionate? It’s going to cause this damage; is it really worth it, in some sense? Does this military action serve the purpose?
And the second criterion is discrimination. And this is designed to limit the amount of damage done to civilians. The rule is not that I may not perform a military action that in fact kills civilians. If that was the rule, then very little war could be conducted, and certainly the Allies could barely have conducted the war against Hitler in 1939 to 1945. So it’s not that one can’t deliberately perform an act that kills civilians. The rule is that I must never intend to kill civilians. In other words, when I am targeting this position, I’m targeting it because it is a military position, not because I want to kill civilians, and I will do all that I can to avoid killing civilians. But there may be occasions when the target is sufficiently important that the killing of civilians or the risk of it is worth taking.