TOKYO REPORT: Japan-S. Korea Ties on Improving Track, but History Issues Remain

Tokyo, Aug. 3 (Jiji Press)–Japanese Prime Minister Sanae Takaichi visited Andong, South Korea, in mid-May for talks with South Korean President Lee Jae-myung, underscoring the steady improvement in bilateral relations after years of strain over historical and territorial disputes. Since Lee took office in June last year, the two leaders have met roughly once every three months. Lee invited Takaichi to Andong, his hometown, after she hosted him for talks in January in her home prefecture of Nara in western Japan. Ties have warmed to the point that a senior Japanese Foreign Ministry official described the relationship as “more stable than we have ever seen before.” Still, sources of friction rooted in history remain unresolved. At the same time, with the global security environment becoming increasingly uncertain, Japan and South Korea face a growing need to deepen defense cooperation. Needing Each Other In 1965, Japan and South Korea normalized diplomatic relations by concluding the Treaty on Basic Relations between Japan and the Republic of Korea and related agreements. They included a settlement of claims related to Japan’s 1910-45 colonial rule of the Korean Peninsula. Even so, relations between the two countries have followed a winding path in the decades since. Ties deteriorated sharply after 2018 South Korean Supreme Court rulings ordered Japanese companies to compensate wartime requisitioned workers from the Korean Peninsula. The dispute pushed bilateral relations to what was widely described as their lowest point since World War II. Relations improved significantly after conservative South Korean President Yoon Suk-yeol took office in 2022. Yoon drastically changed Seoul’s approach to Tokyo and, among other steps, presented a plan to resolve the wartime labor issue. The inauguration of progressive President Lee subsequently raised concerns that ties with Japan might again come under strain. So far, however, Lee has maintained stable relations by pursuing a diplomacy focused on national interest and by largely sustaining the Yoon administration’s approach to Japan. The improvement in Japan-South Korea relations is also evident in grassroots ties and economic activity. The number of people traveling between the two countries reached about 13 million in 2025, setting a record. On the economic front, total bilateral trade, led by semiconductor-related products, has remained robust, exceeding 11 trillion yen annually since 2022. Jo Yang-hyeon, director of the Center for Japanese Studies at the Korea National Diplomatic Academy and an expert on Japan-South Korea relations, said the improvement in bilateral ties reflects changes in the international environment, including developments in the Middle East. The two countries “need each other” and “share a sense of crisis,” he said. Deep-Rooted Public Sentiment Despite the recent friendly atmosphere, challenges are mounting for Japan-South Korea relations. One key issue is defense cooperation. Japan has sought to conclude an acquisition and cross-servicing agreement with South Korea that would enable the two countries to provide each other with fuel, ammunition and other supplies. Lee, however, has said that reaching such an agreement would be difficult, citing “public sentiment.” In South Korea, public opinion shaped by Japan’s colonial rule of the Korean Peninsula remains deeply rooted and continues to influence bilateral ties. Nam Ki-jeong, professor at Seoul National University’s Institute for Japanese Studies, said many of those calling for the resolution of historical issues are supporters of Lee. At the same time, he noted that many citizens are ready to think carefully about various aspects of defense cooperation with Japan. A Japanese government official also sounded cautious, saying, “The embers of historical issues have not gone out.” The day before the May summit, the Japanese government announced that it would conduct DNA testing on remains discovered at the site of the Chosei undersea coal mine in Ube, Yamaguchi Prefecture, western Japan, where people from the Korean Peninsula worked during the war. Takaichi has pursued a diplomatic approach that takes South Korean sensitivities into account. Since taking office in October last year, she has refrained from sending cabinet ministers to the Takeshima Day commemorative ceremony and from visiting Yasukuni Shrine in Tokyo, despite having advocated such moves before becoming prime minister. Japan claims sovereignty over Takeshima, a group of islets in the Sea of Japan effectively controlled by South Korea, where they are known as Dokdo. Yasukuni Shrine is regarded by South Korea and China as a symbol of Japan’s wartime militarism because it honors Class-A war criminals along with the war dead. Japan and South Korea share many strategic concerns, notably China’s increasingly assertive behavior and North Korea’s nuclear and missile development. “We don’t have the luxury of quarreling,” a senior Japanese Foreign Ministry official said. As tensions rise in the region, the key question is how far the two countries can go in strengthening cooperation. The Japanese government’s diplomatic skill is being put to the test. END [Copyright The Jiji Press, Ltd.]