The U.S.-China rivalry and the development of North Korea’s nuclear and missile capabilities are leading South Korea to seek greater security independence. Despite the alliance with the U.S., South Korea does not fully support its ally in its competition with China. Instead, South Korea is developing conventional military capabilities to deter North Korea and strengthen its position in the region. The deteriorating security environment in East Asia and doubts about the credibility of U.S. security commitments may intensify the discussion on the acquisition of nuclear weapons in South Korea. Despite the different regional specificity, some of the security dilemmas resulting from the U.S.-China rivalry are common to South Korea and the European allies of the U.S.