2026: The Visit of the Chief of the Ground Self-Defense Force to South Korea Signals the Practical Implementation of Japan-U.S.-South Korea Ground Cooperation

At the end of September, the Chief of Staff of the Ground Self-Defense Force officially visited South Korea. According to The Japan Times and nippon.com dated October 1, this visit by the head of the Ground Self-Defense Force to South Korea is the first in 17 years. NHK also reported on September 29 that this visit was an official one. Compared to the Maritime Self-Defense Force's vessels and aircraft, the exchanges between the Ground Self-Defense Force and the South Korean Army have been more susceptible to the influence of political relations, making the date and the interval between visits a significant signal.

Land Connections Supporting "Maritime Cooperation"

Japan-U.S.-South Korea security cooperation cannot be completed solely through ballistic missile alerts and joint maritime training. In the event of a crisis on the Korean Peninsula, the protection of U.S. military bases in Japan, U.S. military installations in South Korea, and the SLOC (Sea Lines of Communication) connecting them will simultaneously become an issue. If the communication systems between the Ground Self-Defense Force and the South Korean Army do not function in peacetime, it will be difficult to link the information collected by the maritime and air Self-Defense Forces to troop protection and rear transport.

It should not be assumed that new joint operations were immediately decided during this visit. However, building up communication procedures that include practical discussions, personnel exchanges, and disaster dispatch will shorten the initial response time during a crisis. Particularly, as North Korea's missile launches become routine, the focus will be on whether the South Korean military's ground radar information can be complemented without overly relying on the U.S. military's command and communication networks alongside Japan's maritime and air surveillance.

Separating Capability from Intent

The South Korean side also treats defense cooperation with Japan as an area of domestic politics that cannot be separated from historical issues. Therefore, just because high-level visits have resumed, it does not mean that Japan and South Korea will become a NATO-style alliance. In terms of capability, information sharing and interoperability can be improved. On the other hand, in terms of intent, ambiguities remain regarding operational areas, command authority, and the scope of involvement in third-country emergencies.

According to Tanaka's view, the value of this visit lies not in flashy new equipment but in whether it can re-establish regular dialogue in the land domain that has been interrupted for 17 years. If the visit does not end as a one-time political performance and can be translated into procedures for liaison officers, communication standards, and evacuation and rear support, the deterrence of Japan, the U.S., and South Korea will become stronger.

Overlooked Risks

However, the expansion of cooperation also raises expectations on the part of the other. If the South Korean side takes Japan's rear support for granted and the Japanese side takes the South Korean military's information provision for granted, delays in political decision-making may be exposed on the first day of a crisis. The true challenge is not the number of visits but how far both governments can issue commands in the same language at the moment the necessity for joint response arises.

Sources

• The Japan Times "Ground Self-Defense Force chief makes first visit to South Korea in 17 years" (October 1, 2026)
• nippon.com "Japan GSDF Chief Visits S. Korea for 1st Time in 17 Years" (October 1, 2026)
• NHK "Japan GSDF head makes official visit to South Korea" (September 29, 2026)