The Ground Self-Defense Force Type 25 to Participate in Keen Sword 2026 for the First Time, Changing Southwest Defense
Tanaka TakashiJapan Ground Self-Defense Force Type-25 to Participate in Keen Sword 2026, Transforming Southwest Defense
On October 19, the Japan-U.S. joint exercise "Keen Sword" began on Ishigaki Island, incorporating the Japan Ground Self-Defense Force's long-range Type-25 anti-ship guided missile for the first time. According to Mainichi Shimbun (October 20), the exercise will continue until October 29, with approximately 45,000 Self-Defense Forces personnel and about 12,000 U.S. military personnel participating. This is not just a large-scale exercise; it is a practical attempt to connect missiles deployed in the southwestern islands with U.S. sensors, naval and air force units, and supply networks.
The Significance of a Range of Approximately 1,000 Kilometers
The Type-25 is operated from a vehicle-mounted launcher and has a range of approximately 1,000 kilometers. In this exercise, the assumption was made that targets would be detected and launched at. As reported by ABC News, the U.S. Marine Corps' NMESIS anti-ship missile and MADIS short-range air defense system were also deployed for the first time on Yonaguni Island, while HIMARS was stationed on Ishigaki Island. The essence of this exercise lies in treating Japan's Type-25, the U.S. NMESIS, and HIMARS on the same operational map.
Yonaguni Island is about 110 kilometers from Taiwan, and Ishigaki Island is also close to Taiwan. Traditionally, island defense has often been discussed in terms of troop deployments to protect individual islands. However, with the deployment of long-range missiles, islands will become dispersed nodes that monitor and deny access to straits and shipping routes, rather than fixed positions. This aligns with the Ministry of Defense's training concept for East China Sea and island defense.
Command and Supply More Challenging than Capability
The mere existence of a range of 1,000 kilometers does not complete deterrence. Who will determine the position of maritime targets, at what point in time, and with what level of accuracy? Furthermore, the ability to process U.S.-Japan rules of engagement, target information sharing, launch approvals, and resupply within hours becomes a critical issue. Even if the Type-25 is excellent, if the launchers are isolated, the pressure on the opponent's air defense network will be limited.
This exercise, which included training across land, sea, air, as well as space and cyber domains, is evidence of awareness of this weakness. Seven countries, including France, Germany, the Netherlands, New Zealand, and the Philippines, also participated in part. The increase in participating countries demonstrates political solidarity, while complicating communication methods, supply standards, and information handling. Multinational participation does not automatically equate to responsiveness.
Deterrence Including Island Residents
Keen Sword is perceived as training aimed at China, North Korea, and Russia, but the Chief of Staff for Joint Staff has explained that it does not target specific countries. This is a necessary diplomatic expression. However, the fact that the opening ceremony on Ishigaki Island was not open to the press, and that opposition to the burden of U.S. military bases in Okinawa has reignited over the arrest of U.S. Marines, indicates that military preparedness and political sustainability are separate issues.
In my view, what the Type-25's first participation signifies is not just the fact that "Japan can shoot far," but the intention to integrate the southwestern islands into a Japan-U.S. joint firepower network. However, the true constraint lies not in the missile's range, but in whether understanding from residents, approval from allies, and the accuracy of information can be maintained simultaneously during a crisis. If that collapses, even a range of 1,000 kilometers will revert to being just an expensive number without deterrence.
References
- The Mainichi, “Major Japan-US joint military drills kick off to boost regional defense,” October 20, 2026
- ABC News / AP, “Japan and the US kick off joint drills around islands as regional tensions rise,” October 20, 2026
- Japan Ministry of Defense, Major Training and Exercises of the Self-Defense Forces
The Japan Self-Defense Forces integrated the Type-25 anti-ship missile system into the Keen Sword joint military exercise, which commenced on October 19, 2026, on Ishigaki Island. Approximately 45,000 Japanese and 12,000 U.S. personnel are participating until October 29. The exercise aims to enhance regional defense capabilities by connecting missile systems with U.S. military assets, including NMESIS and HIMARS.
- Type-25 missile system was integrated into the Keen Sword exercise for the first time.
- Approximately 45,000 Japan Self-Defense Forces and 12,000 U.S. Forces are participating in the exercise.
- The exercise aims to connect missile systems with U.S. military sensors and supply networks.
- The Type-25 has a range of approximately 1,000 kilometers and is launched from vehicle-mounted platforms.
- The exercise includes participation from seven other countries, indicating a multinational effort.