Is war ever right?

Almost every country that has gone to war has said it was defending itself, or somebody else, from something. That is not because the claim is usually false. It is because the test exists, and everybody knows it.

The test has a list. There must be a real wrong. The force must be a last resort. It must be declared by whoever is properly entitled to declare it. The intention must be to restore peace rather than to grab something. The harm done must not exceed the harm prevented. And, in the modern version, the fighting itself must distinguish between people who are fighting back and people who are not.

Two responses are worth taking seriously. Gandhi’s is that the list smuggles violence in as a solution, and that the means used determine the result — a war fought by slaughter cannot end in a fair peace. The other is Walzer’s, and it is the one that tends to matter more in practice: how does the ordinary soldier know? He is told his war is just by the people who would lose if it were not. The moral burden lands on somebody who has no way to check.

Which leaves a question that is quite hard and very worth asking early. If the conditions are real, they should sometimes say no — and almost everybody’s own country, at some point, has fought a war that failed them. Being able to say which war, without being told, is the test of whether you actually hold the rules or just hold them for your own side.

Try it

Write the rules you would want a country to satisfy before it fights. Then test them: does your own country's past pass? Would you accept them if the answer was no?

What do you think?

Do you think there is a right answer to this question?

Yes, I think soNo — and here's whyI'm not sure yet

Talk about it

• Is it worse to start a war or to let a wrong continue?
• Can a war ever be fought fairly?
• Who should decide?

Yes, but… — the arguments people actually make

• War is always wrong, whatever the reason.

  Then you must also accept standing by while a defenseless group is destroyed, if force is the only thing that would stop it. That is a real position, and it is much heavier than it sounds.

• If it's a last resort, almost nothing qualifies.

  That is the point of saying it — which is exactly why every government claims it was the last resort. A test that is always passed by the person being tested is not doing much work.

• The rules only matter to the side that follows them.

  True, and worth stating plainly: restraint imposed on one side only is a disadvantage, not a moral victory. The argument for restraint has to be that it holds even when it is not returned.

What other philosophers think

• AugustineArgued that a war can be justified as the restoration of peace, but only when waged by proper authority, for a just cause, with the right intention — a list that has been argued about ever since.
• Thomas AquinasTurned that into formal conditions, including that force must be proportionate and used only as a last resort.
• Moses MaimonidesHeld that some wars are obligatory and others merely permitted, and set limits on how even an obligatory war may be fought.
• Mohandas GandhiArgued that non-violent resistance is not passivity but a harder kind of force, and that means are never separable from ends.
• Michael WalzerDefended the moral difference between soldiers and civilians, and asked how a soldier can know whether the war he is ordered into actually meets the conditions.

If you want to go further

• The City of God — AugustineThe just war idea appears in scattered passages; Book XIX is the most quoted.
• Summa Theologica — Thomas AquinasThe 'just war' conditions are set out in a few clear articles and are still the reference point.
• Just and Unjust Wars — Michael Walzer1977. The book that made the ethics of war a serious subject again.

Most of these were written for adults, which is why it is worth reading them with someone older.