Based on an innovative theory of international law, Janina Dill's book investigates the effectiveness of international humanitarian law (IHL) in regulating the conduct of warfare. Through a comprehensive examination of the IHL defining a legitimate target of attack, Dill reveals a controversy among legal and military professionals about the 'logic' according to which belligerents ought to balance humanitarian and military imperatives: the logics of sufficiency or efficiency. Law prescribes the former, but increased recourse to international law in US air warfare has led to targeting in accordance with the logic of efficiency. The logic of sufficiency is morally less problematic, yet neither logic satisfies contemporary expectations of effective IHL or legitimate warfare. Those expectations demand that hostilities follow a logic of liability, which proves impracticable. This book proposes changes to international law, but concludes that according to widely shared normative beliefs, on the twenty-first-century battlefield there are no truly legitimate targets.

'Why do states obey international law? How and why do the laws of war constrain state behavior? Legitimate Targets explores the tensions, dilemmas, and power of international humanitarian law to shape the practice of war. This tour de force - rooted in insightful readings of military doctrine, international law, the practice of war, and dozens of interviews with military professionals - is a brilliant synthesis that will enable students of war to understand how and why the nature of war is changing.' Neta C. Crawford, Boston University, author of Accountability for Killing: Moral Responsibility for Collateral Damage in America's Post-9/11 Wars
''Can war be effectively regulated by international law?' In answering this vital question, Janina Dill offers a new and sophisticated understanding of the very nature of law and the way it creates effects in the world. Law is a compromise between utility and morality, between military pragmatism and humanitarianism, but it is also dynamic. It evolves through use and application to new challenges of war-fighting. Dill's excellent book will challenge long-held views about both law and how wars are fought.' Martha Finnemore, George Washington University

Janina Dill is a lecturer in the Department of Politics and International Relations at the University of Oxford.