The Koreas | Diplomacy | East Asia

Koizumi’s First Trip to Seoul: A Sign of Cautious Japan-South Korea Reconciliation

While the latest Japan-South Korea defense ministers’ meeting shows an obvious trajectory of rapprochement between the two neighbors, it also exposes certain boundaries in their defense cooperation.

Japanese Defense Minister Koizumi Shinjiro paid a two-day visit to Seoul on June 27-28 and held direct talks with his counterpart Ahn Gyu-back. This was Koizumi’s first official trip to South Korea in his current position, reciprocating Ahn’s visit to Tokyo in January. For the two leaders personally, it marked their fourth face-to-face meeting since last November, out of six encounters to date in total. Unprecedentedly, the two ministers jointly visited South Korea’s Black Eagles aerobatic team at the Wonju Air Base. It was the first time a foreign defense minister had done so.

The last visit similar to Koizumi’s recent trip was in September 2025, when then-Japanese Defense Minister Nakatani Gen traveled to Seoul to meet his South Korean counterpart Han Min-koo. While Nakatani’s visit symbolized the end of a decade-long diplomatic hiatus between the two countries, the latest talks also marked a significant milestone for their relations. It was the second time in history, repeated after 23 years, that Japanese and South Korean defense ministers have exchanged visits within a single year.

Beyond its symbolic meaning, Koizumi’s rare talks with Ahn in Seoul also signaled the steady strengthening of high-level bilateral defense cooperation between the neighbors. Previously, on May 7, Japan and South Korea held their first “2 2” vice-ministerial talks between their foreign and defense ministries in Seoul, marking an upgrade from the original director-general level launched in 1998. Koizumi’s trip also came just weeks after Tokyo and Seoul resumed joint maritime search-and-rescue exercises (SAREX) following a nine-year hiatus. These signs indicate a remarkable normalization of cooperation between the two countries’ defense authorities since the 2018 incident involving a South Korean naval vessel and a Japanese Maritime Self-Defense Force patrol plane.

The joint statement released after the talks said the two sides would continue developing cooperation between their aerobatic teams (Blue Impulse and Black Eagles). This was considered an important step forward, given that Japan had previously refused to provide refueling support for the Black Eagles in November 2025 due to the Dokdo/Takeshima territorial dispute; one of the aircraft in the Black Eagles had taken part in a drill over the islets. Although this does not necessarily imply that South Korean military aircrafts will receive refueling support from Japan regularly, it remains a notable detail, as the disputed islets have long been a major obstacle in bilateral relations.

The two ministers also reaffirmed their commitment to “complete denuclearization of the Korean Peninsula........

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