Full Idea
Just wars are limited wars; there are moral reasons for the statesmen and soldiers who fight them to be prudent and realistic.
Gist of Idea
For moral reasons, a just war must be a limited war
Source
Michael Walzer (Just and Unjust Wars [1977], 07)
Book Reference
Walzer,Michael: 'Just and Unjust Wars' [Penguin 1984], p.122
A Reaction
This is rather profound, I think. Watch closely the behaviour of the good guys when they are winning the war. In general, to know someone's moral principles, the best indicator is how they behave when they have power.