Thinking about and planning for large-scale war between conventional, World War II–style armed forces for symmetrical warfare and strategic nuclear war predate and postdate the contemporary period. The traditional roles of these forces were developed with the end of the Cold War, and only the United States retains a robust traditional capability, which it proposes to augment through force modernization. Critics say these large European-style forces are anachronisms in a world of shadowy, asymmetrical threats. Before assessing these criticisms, it is necessary to describe “legacy” forces and missions from the Cold War, first nuclear forces and then conventional forces, and the residual problems associated with each. Special operations forces and missions have their origins in the Cold War and before and have become a more prominent factor in the contemporary environment. These changing conditions also affect the nature of forces, notably in military manpower.