The importance of strategy and national security policymaking have become increasingly salient over the past few years. For South Korea, located at the intersection of great powers, these topics are particularly important. This thesis examines South Korea’s national security strategy (NSS) and the broader Northeast Asian context, covering roughly the time period from 2002 to 2019 over the four South Korean presidential administrations who have publicly released their governments’ NSS. It focuses more on unpacking the country’s holistic NSS over time and the underlying strategic logic behind their formulation, rather than on evaluating the policy or strategic outcomes.

This study finds that overall, there has been greater continuity than change in South Korea’s NSS. Specifically, there has been strong thematic continuity in terms of the core areas represented by the ends, means, and ways of national strategy; consistently covering key areas such as inter-Korean relations, the US-ROK alliance, and the relations with the three neighboring powers – China, Japan, and Russia (external dimension); and promoting liberal democratic values, economic prosperity, strengthening general national security foundations (internal dimension). The broader NSS ends such as peace and prosperity on the peninsula or the broader region, and the means to achieve them (e.g. diplomacy, military) have also largely remained consistent.

Next, this research finds that the biggest drivers of South Korea’s NSS have been (1) the strategic environment and (2) the individual administrations’ values and policy priorities – in that order of importance. In other words, given its inherently and consistently challenging geopolitical situation, South Korea’s level of agency and flexibility regarding its NSS have been inversely proportional to how high the tensions are in its strategic environment; after which individual presidents matter most as the subsequent influential factor.

This study makes several contributions. First, it furthers our critical understanding of South Korea’s NSS, a subject that has been largely absent in the existing literature to date. Focusing on this holistic strategic dimension offers new perspectives on key issues, such as that on a broader level, differences between administrations based on political party affiliation were less than expected, except for a few key policy areas (notably North Korea and Japan). Next, this study highlights the importance of the individual factor, particularly in South Korea but also as a unit of analysis when considering strategy and policymaking. Finally, it adds important data points – South Korea and (to a lesser extent) Northeast Asian States (Japan, China, Russia) – and their approaches to NSS, enhancing our overall understanding of how non-western and/or non-great power states approach their broader national-level security strategies.