Double-Double Effect

"Double effect" is a mitigating element in just war theory regarding the killing of civilians. As the claim goes, killing noncombatants unintentionally in an attack on combatants can be justified if precautions are generally taken not to kill noncombatants and even if noncombatant deaths are foreseen as the unfortunate result of a military attack on combatants. Michael Walzer takes the doctrine further and argues that a military must take risks not to kill noncombatants. The effort must be serious, not spurious.

The whole thing is complicated further when we're talking about humanitarian intervention as opposed to outright war. Verbum Ipsum:

This post by the Bull Moose blogger (via Marvin) brings to mind a point made by Robert Holmes in his excellent On War and Morality (I don't have the book in front of me, so I may not get all the details right).

Pacifists and anti-interventionists are often criticized for their unwillingness to take up arms in the defense of the innocent. According to interventionists, the blood of those innocents is on their hands.

However, Holmes points out, interventionists usually deny that they are morally responsible for the innocent lives lost in the course of waging war. But how, he asks, can they fail to be responsible for the deaths of people they actually kill, while pacifists are held responsible for the deaths of people they had no part in killing?

In other words, if double effect is sufficient to get the "warist" off the hook for the innocent deaths the war he supports causes, it should be more than sufficient to get the pacifist off the hook for the deaths he merely fails to prevent by refusing to wage (or support) war....