Future of Korea-Japan relations under PM Ishiba
On Oct. 1, Japan confirmed Shigeru Ishiba as its new prime minister. Ishiba’s victory in the ruling Liberal Democratic Party (LDP) leadership race came as a surprise to many, but his election was received warmly in nearby South Korea. President Yoon Suk Yeol and Ishiba held their first phone call on Oct. 2, in which the leaders agreed to make the “good relationship” sustainable and continue their in-person visits.
Throughout his career, Ishiba has emphasized the value of the bilateral relationship, noting in 2019 that deteriorating relations between Tokyo and Seoul do not add to the peace and stability of the region. He has also been keen to understand South Korea’s position on historical issues and is reluctant about visiting Yasukuni Shrine — long a contentious issue between Japan and neighbors like China and South Korea — as prime minister.
This will likely be a boon for sustained cooperation with the Yoon administration, as Ishiba aims to carry forward former Prime Minister Fumio Kishida’s achievements in the bilateral space including restarting working-level defense talks for the first time in nine years and enhancing cooperation to areas like economic security and advanced technologies such as quantum computing.
Ishiba’s new Cabinet also includes a supporting cast that shares the prime minister’s worldview, including Foreign Minister Takeshi Iwaya, Defense Minister Gen Nakatani and Akihisa Nagashima, a special adviser to the prime minister on security issues.
The security-oriented lineup, with three former defense ministers, combines a wealth of experience communicating with Seoul on challenging issues and pursuing level-headed diplomacy for improved relations. Iwaya, for instance, defended bilateral relations during the 2019 radar lock-on dispute, calling for efforts toward “future-oriented defense cooperation.” Meanwhile, Nakatani is the vice chair of the Japan-Korea Parliamentarians’ Union, and Nagashima has been active in the Japan-ROK Cooperation Committee. The core of the new Cabinet’s diplomatic presence will ensure continued dialogue toward further strengthening ties.
Still, skepticism exists on both sides. On one hand, significant segments of the Korean political landscape and academic community remain skeptical about further improvements in bilateral relations, emphasizing the need for concrete actions addressing historical grievances and questioning the new administration's capacity for change.
The main opposition Democratic Party of Korea has stressed that Ishiba must offer an official and sincere apology for historical issues before any substantial bilateral improvements can occur. This stance appears to leverage Ishiba's relatively moderate approach to historical disputes, although such an apology is unlikely to materialize.
Korean experts and think tanks have also pointed out Ishiba's perceived limited support within his own party. This raises questions about both the potential longevity of his administration and its ability to implement policies that could meaningfully create regional impacts.
On the other hand, some conservative Diet members in the LDP argue that all progress made under the Yoon-Kishida governments will easily be reversed under a liberal South Korean government. These concerns are warranted but should not stop the pursuit of cooperation.
As a defense expert, Ishiba is bound to understand that the value of cooperation in the face of a mutually severe regional security environment — including concerning activities by North Korea, Russia and China — trumps the negative sentiment building over years of deadlock. At least while the Yoon and Ishiba governments are in place, we can expect cooperation to continue.
Another concern some have raised is Ishiba’s hawkishness, which will likely be welcomed by the security-oriented Yoon administration but feared by some as the return of a militaristic Japan, similar to how then-Prime Minister Shinzo Abe was perceived.
The concerns may be stoked further by Ishiba’s proposal of an “Asian NATO,” which would establish a collective security architecture similar to Europe’s NATO between U.S. allies in the region including South Korea and Japan. A NATO-style commitment to defend member state from armed attack would be a significant leap in trust and cooperation for Seoul and Tokyo — something that both sides as well as the United States may be unprepared for. South Korean Foreign Minister Cho has already made it clear that the idea lacks sufficient substantiation to warrant discussion, signaling Seoul's cautious stance on the matter.
So far, the idea is nothing more than a hypothetical concept on paper and will likely face numerous hurdles before reaching Seoul. New Foreign Minister Iwaya pointed out the constitutional hurdle over collective self-defense, stating that the idea would be considered from a “medium- to long-term perspective.” However, one of Ishiba’s early diplomatic objectives may include clarifying the contours of this concept to Washington, Seoul and other regional capitals.
The three years under Yoon and Kishida ushered in a historic period of friendship between South Korea and Japan. Prime Minister Ishiba will now be tasked with continuing to engage with the Yoon administration toward deepening security — and increasingly economic and cultural — ties between the two countries. On the eve of the 60th anniversary of diplomatic ties, South Korea and Japan can be expected to take further steps toward enhancing tangible cooperation and mutual understanding of each other under a Japanese administration keen to pick up where the former administration left off.
Perhaps the first order of business, as Park Cheol-hee, South Korea’s new ambassador to Japan, proposes, could be updating the 1998 joint declaration, which preaches the need for solid relations while mutually respecting each other’s positions and opinions.
Rintaro Nishimura is a Tokyo-based Associate with the Asia Group, a strategic advisory firm assisting businesses throughout Asia. Park Jin-wan is a nonresident James A. Kelly Korea Fellow at Pacific Forum.