The principle security threat of the past several centuries—war between or among major powers—is gone. Two new types of threats have been introduced into the global security arena. Violent nonstate actors and other indirect political, economic, and social causes of poverty, social exclusion, corruption, terrorism, transnational crime, the global drug problem, and gangs are a few examples of these “new” threats to global security and stability. More and more, national security implies protection—through a variety of nonmilitary and military ways and means—of popular interests that add up to well-being. This broadened definition of the contemporary security problem makes the concept so vague as to render it useless as an analytical tool. The genius of Ambassador Stephen Krasner, however, helps solve the problem. His orienting principle for foreign policy and military management (responsible sovereignty/legitimate governance) focuses on the need to create nation-states capable of legitimate governance and to realize stability, security, and well-being for citizens. This concept has serious implications for the transition and relevance of armed forces and other instruments of power, as well as foreign policy. Thus, we: 1) define the contemporary security dilemma and the larger principle of Krasner’s responsible sovereignty; 2) outline the major components of a legitimate governance paradigm; 3) discuss some considerations for foreign policymaking and military management; and, 4) argue that substantially more sophisticated security-stability concepts, policy structures, and decision and policymaking precautions are necessary if the United States is to play more effectively in the security arena now and in the future.