Joseph S. Nye Jr. provides a concise, penetrating analysis of the role of ethics in U.S. foreign policy after World War II. Nye works through each presidency from FDR to Trump and scores their foreign policy on three ethical dimensions: their intentions, the means they used and the consequences of their decisions. He also evaluates their leadership qualities, elaborating on which approaches worked and which did not. Nye shows that each president was not fully constrained by the structure of the system and actually had choices. He further notes the important ethical consequences of nonactions, such as Truman's willingness to accept stalemate in Korea rather than use nuclear weapons. Most importantly, he points out that presidents need to factor in both the political context and the availability of resources when deciding how to implement an ethical policy and will need to do so even more in a future international system that presents not only great power competition from China and Russia but a host of transnational threats: the illegal drug trade, infectious diseases, terrorism, cybercrime and climate change.