In war people get killed. They also get wounded and mutilated, sometimes horribly. They may be held in confinement against their will and forcibly prevented from escaping. Even as civilians, they may be killed in an attack on a legitimate target. And all of this is perfectly legitimate. While there are strict controls on what may be legally done in war, it inevitably entails violence and suffering. We can seek to reduce this aspect, but we can never turn war into a video game, and it is dangerous and selfdeluding to imagine that we can. Thus, the consideration of war crimes raises issues of proportionality and balance. Moreover, many illegal acts of war have a sound military justification behind them and, if practiced, might well end a war or battle more quickly, and with fewer casualties, than would otherwise have been the case. When we add to this the fact that many acts of war that are illegal today were thought acceptable, if not praiseworthy, in the past, then the moral and ethical—as well as the legal and practical—issues raised by the notion of war crimes are complex, relative, and murky.
Partly this is because of the curious fashion in which the laws of war have been elaborated, in two distinct ways and according to two distinct traditions. On the one hand, the military has always recognized the need for limitation. Notwithstanding the tendency to see war as just episodes of mindless slaughter and wanton destruction, military professionals have, in fact, often tried to limit the amount of violence used for practical reasons. The military, after all, is about controlled violence. To continue fighting after an enemy seeks to surrender, or after a peace treaty has been signed, for example, could involve unnecessary casualties and frustrate political aims. Economy of force is generally a good military principle, and professionals will respect a general who wins a cheap victory more than one who