In this excellent study, Miller brings to bear scholarly rigor and his recent experience as the U.S. National Security Council’s director for Afghanistan and Pakistan to assess U.S. and UN efforts to rebuild failed states through armed intervention. Drawing on evidence from such missions in Germany after World War II and more recent attempts in Nicaragua, Liberia, Sierra Leone, Afghanistan, and elsewhere, Miller argues there is no master strategy that will work in all instances. In successful cases, such as the Allied occupation of Germany and the UN’s postconflict reconstruction operations in Mozambique and Namibia, the key was correctly matching the strategy to the problem. The most important choices that would-be nation builders must make are whether to impose direct rule over a failed state and whether to assume full responsibility for its security. Miller argues that the ongoing failure in Afghanistan is a result of NATO and the United States’ adopting the wrong strategy for rebuilding Afghan state security forces. Despite his firsthand experience of the struggle in Afghanistan, Miller delivers a surprisingly upbeat assessment of armed state building. His book displays an admirable clarity in its evidence and analysis, although it is worth wondering whether powerful Western states can reliably behave as carefully as Miller advises.