Korea’s security had always been the highest of Park’s priorities, but after the pronouncement of the Nixon Doctrine and the subsequent fall of Vietnam, Park became even more concerned, especially about the strength of the US security commitment to the Korean peninsula. This chapter examines Park’s response to this concern and how that ultimately led to severe tension between himself and the ambivalent President Jimmy Carter, and perhaps even to his own assassination. Park’s initial strategy was to establish a Korean-resourced military modernization capability through what was known as the “Yulgok Operation.”