When is the use of military force by a nation morally justified? Why has the long accepted moral requirement to protect civilians from intentional attack eroded in recent years? How can the tendency toward unrestrained warfare between parties with major cultural differences be controlled? In this thought-provoking book, James Turner Johnson refocuses the moral analysis of war on the real problems of today’s armed conflicts. Moral debates about nuclear war and annihilation fail to address the problems of actual contemporary uses of military force, Johnson argues. We must address the type of armed conflict that has emerged at the end of the twentieth century: local wars—often inflamed by historical, ethnic, or religious animosities and usually fought with conventional weapons that can be carried by individual fighters. Johnson sets out a moral basis for understanding when armed force can be justified. He analyzes specific problems posed by contemporary warfare: the question of military intervention to ameliorate or end conflicts, the question of warfare against noncombatants, the problem of cultural differences inflaming conflict, and the tension between those who would punish war crimes and those hoping to reconcile adversaries. The author concludes with a discussion of how to reshape and renew an international consensus on the proper purposes and limits to war.