Japan–Korea Tensions

The Colonial Legacy

Japan colonized Korea from 1910 to 1945, a period that remains the central wound in the bilateral relationship. Japanese colonial rule suppressed Korean language and culture, forced Koreans to adopt Japanese names, conscripted hundreds of thousands of Koreans into forced labor in Japanese mines, factories, and construction projects, and coerced an estimated 200,000 women — euphemistically called 'comfort women' — into sexual slavery for the Japanese military.

The 1965 Treaty on Basic Relations between Japan and the Republic of Korea normalized diplomatic ties and included a $500 million economic aid and loans package that Japan considered comprehensive settlement of all colonial-era claims. South Korea used these funds to fuel its industrialization. However, the treaty was negotiated between authoritarian governments without public consultation, and many Koreans — particularly victims of forced labor and sexual slavery — never accepted that their individual claims were extinguished.

This disagreement over whether the 1965 settlement resolved all claims has been the source of recurring crises. In 2018, South Korea's Supreme Court ruled that individual forced laborers could sue Japanese companies for compensation — a ruling Japan considered a violation of the treaty. The dispute escalated into a trade war, with Japan restricting exports of critical semiconductor materials to South Korea and removing it from a preferential trade list.

The Comfort Women Dispute

No issue inflames Korean-Japanese relations more than the comfort women. Beginning in the early 1990s, surviving victims came forward publicly, demanding acknowledgment and apology from the Japanese government. Japan has issued multiple statements of remorse — most notably the 1993 Kono Statement acknowledging military involvement and the 2015 agreement with South Korea that included a formal apology and a $8.3 million fund for survivors.

But each apparent resolution has unraveled. Korean activists argue that Japan's apologies have been inadequate, inconsistent, and undermined by subsequent statements from Japanese politicians denying or minimizing the coercion involved. Statues commemorating comfort women, installed outside Japanese embassies in Seoul and other cities, have become flashpoints — Japan demands their removal as a condition of the 2015 agreement; Korean civic groups refuse.

The Moon Jae-in government effectively dissolved the 2015 agreement's foundation in 2018. The issue operates on multiple levels simultaneously: it is a genuine human rights demand by aging survivors, a domestic political tool in both countries, and a symbol of unresolved historical justice that neither government can easily resolve without facing domestic backlash.

Dokdo/Takeshima and Strategic Complications

South Korea controls the Dokdo islands (called Takeshima in Japan) — a cluster of rocky islets in the Sea of Japan/East Sea. Both countries claim sovereignty based on competing historical records. The islands themselves are tiny and largely uninhabitable, but they carry enormous symbolic weight and confer exclusive economic zone rights over surrounding fishing grounds and potential seabed resources.

The territorial dispute poisons cooperation on issues where Japan and South Korea have aligned interests. Both are US treaty allies, both face a nuclear-armed North Korea, and both are wary of China's growing assertiveness. The US has long pushed for trilateral security cooperation, and progress was made under the Yoon Suk Yeol government with the 2023 Camp David trilateral summit. However, the relationship remains vulnerable to historical triggers — a Japanese politician's visit to the Yasukuni Shrine (which honors war criminals alongside ordinary war dead), a new textbook controversy, or a court ruling on wartime compensation can rapidly undo diplomatic progress.