What is the future of the U.S.-ROK alliance? Will it continue to serve the needs of both countries? Will diverging interests on some issues such as South Korean participation in U.S. geopolitical activities to contain China weaken it? Might South Korea attempt to develop a more independent foreign policy? This paper considers these questions against the background of major tensions during the Moon Jae-in-Donald Trump era over trade, defense cost-sharing, North Korean denuclearization, the U.S. Terminal High Altitude Area Defense system and the rise of China. The main argument of the paper is that the Korean economic miracle and a reassertion of Korean nationalism are pushing Seoul to develop greater policy autonomy but that the bilateral alliance remains so important to it for economic, security, and historical reasons that it is likely to endure, albeit in a modified form in which new purposes are created and Seoul is given greater responsibilities by the United States to whom South Korea plays an important role in its Asian “hub and spoke” alliance structure. The paper also argues that that structure may be the wrong one for dealing with the North Korean nuclear weapons issue and that a new collective security or shared security governance mechanism should be created in which stakeholders in Northeast Asian security, including China and Russia, should be members.