Executive Summary
This thesis from the Naval Postgraduate School examines the durability of Japan-South Korea bilateral security relations, focusing on factors like political leadership, regional threat perception, and U.S. pressures. It analyzes how recent cooperative efforts, particularly since 2022 and the Camp David Summit, have contributed to institutionalizing security cooperation despite historical tensions. The study also explores potential
Why It Matters
This document is crucial for defense analysts as it assesses the factors influencing the stability and future trajectory of security cooperation between two key U.S. allies in the Indo-Pacific, directly impacting regional deterrence against China and North Korea.
Key Takeaways
- Pro-relationship political leadership, such as former President Yoon and Prime Minister Kishida, significantly drove cooperative efforts, including the Camp David Summit.
Source evidence · PDF page 56
First, a combination of pro-relationship-building political leadership, particularly South Korea’s former President Yoon and Japan’s former Prime Minister Kishida, drove monumental cooperative efforts, like the Camp David Summit, and incremental cooperative efforts, such as regular bilateral heads-of-state meetings.
- Shared perceptions of rising threats from North Korea and China have pushed both nations towards greater bilateral and trilateral security cooperation.
Source evidence · PDF page 45
Another driver of stronger Japan-South Korea cooperation—though not automatic or exclusive—has been both countries’ heightening perceptions of threat in their share region. With North Korea continuing to be a major security concern, South Korea and Japan have utilized the Camp David trilateral agreement and joint statements to better align deterrence objectives.
- Unprecedented military exchanges and defense agreements since 2023 indicate a potential for
Source evidence · PDF page 51
The degree of bilateral cooperation since 2023 has been unprecedented. South Korea and Japan have revamped military exchanges, to include unprecedented language and defense agreements, even outside of U.S.-driven efforts and newly promoted trilateral exercises.
Strategic Relevance
The analysis of Japan-South Korea security relations is strategically important for understanding regional stability in the Indo-Pacific, particularly concerning deterrence against North Korea and China, and the effectiveness of U.S. alliance structures. The institutionalization of cooperation through