Modern war is law pursued by other means. Once a bit player in military conflict, law now shapes the institutional, logistical, and physical landscape of war. At the same time, law has become a political and ethical vocabulary for marking legitimate power and justifiable death. As a result, the battlespace is as legally regulated as the rest of modern life. In , David Kennedy examines this important development, retelling the history of modern war and statecraft as a tale of the changing role of law and the dramatic growth of law's power. Not only a restraint and an ethical yardstick, law can also be a weapon--a strategic partner, a force multiplier, and an excuse for terrifying violence. Kennedy focuses on what can go wrong when humanitarian and military planners speak the same legal language--wrong for humanitarianism, and wrong for warfare. He argues that law has beaten ploughshares into swords while encouraging the bureaucratization of strategy and leadership. A culture of rules has eroded the experience of personal decision-making and responsibility among soldiers and statesmen alike. Kennedy urges those inside and outside the military who wish to reduce the ferocity of battle to understand the new roles--and the limits--of law. Only then will we be able to revitalize our responsibility for war.