Sixty Years of Japan and South Korea’s Normalisation of Relations
Dr. Anudeep Gujjeti
The year 2025 marks 60 years of normalisation of relations between South Korea and Japan. Following the animosity and hostility of post-war, Japan and the Republic of Korea (South Korea) advanced towards cordial ties by signing the normalisation treaty and associated papers on June 22, 1965, in Tokyo. There was a prevailing worry among Koreans that the restoration of normal relations would once more subject the South Korea to Japan’s economic and political hegemony. Conversely, the opposition party in Japan deemed it impractical at that time for Japan to choose the Republic of Korea from the fragmented nation of Korea as its ally. The Governments of Japan and the South Korea successfully overcame parliamentary resistance to secure the majority required for ratification of these documents. The ratification instruments were exchanged in Seoul on December 18, 1965.
The 60th anniversary comes at a time when both nations are undergoing significant domestic political makeover and as the geopolitics of the world is rapidly evolving at an unprecedented pace. In recent years, Japan and South Korea’s strategic importance has grown exponentially due to China’s increasing assertiveness in the surrounding waters of both the nations, North Korea’s escalating nuclear adventurism, and the United States (US) growing focus on its national interests, accompanied by a retreat from global commitments. Moreover, South Korea sent $28.4 billion worth of goods to Japan in 2023 whereas Japan exported $42.7 billion to South Korea in 2023. However, in the last five years, the exports from Japan to South Korea as well as from South Korea to Japan have declined at an annualised rate 4.48% and 1.38% respectively.
Historically, South Korea has had its reasons to harbour hostility towards Japan. Japan seized South Korea in 1910. The subsequent colonial governance involved the “Japanization of Korean society,” encompassing cultural suppression, assimilation initiatives, and more measures. The circumstances deteriorated during World War II and the Second Sino-Japanese War between 1937 and 1945, as several Koreans fell prey to forced labour, the Japanese comfort women program or conscription into the Japanese military which coerced many into sexual slavery in military brothels. These memories remained in the minds of South Koreans for decades to come even after both the nations normalised their relations. Only after Yoon Suk Yeol became the President of South Korea in 2022 that relations between both the nations saw a positive trajectory.
In 2023 at a joint news conference following the summit between Japanese Prime Minister Kishida and South Korean President Yoon Suk Yeol, Yoon stated that the South Korean government’s stance on wartime forced labourers is grounded in the “1965 claims agreement” established during the normalisation of diplomatic relations with Japan. Yoon clarified that the South Korean government’s conventional interpretation of the wartime forced labour issue diverged from that of the Supreme Court of South Korea. While the relations were normalising at the political front, President Yoon was impeached following a failed declaration of martial law which made Japan worry about the trajectory relations between both the nations.
Moreover, Japan on its part is facing another political crisis. Prime Minister Ishiba got elected in November 2024 with a fractured mandate which is not enough to pass legislations on its own. Ishiba must obtain opposition backing to enact legislation and the national budget, so creating an environment of increased political uncertainty. Additionally, Ishiba recently opted to distribute ¥100,000 gift coupons to 15 newly elected members of the Liberal Democratic Party (LDP). The opposition and media swiftly criticised the action, with many parties demanding the resignation of the prime minister. This comes right after Prime Minister Ishiba met President of United States after a lot of planning which involved Japan's top US-Japan relations experts had to persuade Ishiba, the country's unexpected prime minister, to follow the plan for his early February encounter with Trump in order to insulate Japan from the Trumps’ tariff game.
Moreover, Japan and South Korea are witnessing a regional order which has undergone unprecedented changes in the form of Chinese incursions into waters claimed by Japan and other regional countries like Philippines and Taiwan upending the established regional order. In order to fulfil its “reunification” goal, China in 2024 alone conducted more than 3000 incursions into Taiwan’s air space raising concerns both in Japan and South Korea. While at the same time both Japan and South Korea are wary of Trump’s policy of engaging less in the multilateral forums which might inadvertently affect the US security umbrella provided to these both nations.
The increase of Japanese defence budget to two percent of its GDP by 2027 falls within the context of rising threats from North Korea, China and Russia with US reconsidering its multilateral engagement. Given these challenges there is need for both Japan and South Korea to strengthen their bilateral relationship driving past the domestic compulsions and act together to address the regional challenges in the domains of economy and security.
Dr. Anudeep Gujjeti is Assistant Professor at the Center of Excellence for Geopolitics and International Studies, REVA University, Bengaluru.
