The CBC's DNTO briefly cited this great bit of Shakespeare's King Henry V in a good piece on cinematic representations of war. It's as relevant a consideration of the moral justifications for war as I've seen while plowing through thousands of words of commentary. (All the more pertinent, since the majority of Americans seem to believe they are following a king as his subjects, and not free, morally responsible individuals.)

KING HENRY. By my troth, I will speak my conscience of the King: I think he would not wish himself anywhere but where he is.

BATES. Then I would he were here alone; so should he be sure to be ransomed, and a many poor men's lives saved.

KING HENRY. I dare say you love him not so ill to wish him here alone, howsoever you speak this, to feel other men's minds; methinks I could not die anywhere so contented as in the King's company, his cause being just and his quarrel honourable.

WILLIAMS. That's more than we know.

BATES. Ay, or more than we should seek after; for we know enough if we know we are the King's subjects. If his cause be wrong, our obedience to the King wipes the crime of it out of us.

WILLIAMS. But if the cause be not good, the King himself hath a heavy reckoning to make when all those legs and arms and heads, chopp'd off in a battle, shall join together at the latter day and cry all 'We died at such a place'- some swearing, some crying for a surgeon, some upon their wives left poor behind them, some upon the debts they owe, some upon their children rawly left. I am afeard there are few die well that die in a battle; for how can they charitably dispose of anything when blood is their argument? Now, if these men do not die well, it will be a black matter for the King that led them to it; who to disobey were against all proportion of subjection.