First Operation of Type-25 in Keen Sword 2026: Japan-U.S. Alliance Moves to Combat Readiness in the Southwestern Islands

The opening ceremony of Keen Sword 2027, held on October 19 at the Japan Ground Self-Defense Force base in Ishigaki Island, did not appear to be just a routine Japan-U.S. joint exercise. This was because Commander Takaki Tahara of the Joint Operations Command delivered a speech on an island approximately 270 kilometers from Taiwan, incorporating not only land, sea, and air operations but also space and cyber domains into a single exercise. The exercise will continue until October 29.

This time, approximately 57,000 personnel are participating, including about 45,000 from the Self-Defense Forces and about 12,000 from the U.S. military. Seven countries, including France and Germany, are also participating, with five of them being first-time participants. While centering on Japan-U.S. bilateral training, the concept of connecting the southwestern islands to a multilateral information and logistics network is beginning to take a fairly concrete form.

The Significance of Type-25's 1,000 Kilometer Range

Most noteworthy is that the Type-25 anti-ship guided missile, which was deployed in March of this year, will be used in the exercise for the first time. Launched from a vehicle-mounted launcher, it has a range of approximately 1,000 kilometers. This training will include a series of scenarios for detecting targets and firing.

The value of this weapon is not merely its long range. The effect of sea denial is only realized when launchers dispersed across the islands, target information from aircraft and naval vessels, and joint command and control, including the U.S. military, are interconnected. The Type-25 is just a part of this, but it indicates that Keen Sword has shifted from being a "platform to showcase deployment" to a "platform to connect detection, judgment, and firing."

Separating Capability from Intent

The political message of deterrence against China is clear. However, even with the deployment of 1,000-kilometer missiles, if launchers, communication networks, and supply bases cannot be kept operational during the early stages of a crisis, the capability remains just a number. In the southwestern islands, ammunition transport, fuel, runway and port restoration, and evacuation of island residents are all included in the same operational plan. The more emphasis placed on long-range strikes, the relatively greater the vulnerability of rear support becomes.

Moreover, while the participation of countries like France and Germany is welcome, an increase in participating nations also raises the need for coordination on information-sharing authority, communication standards, and rules of engagement. Being able to coordinate during the exercise is one thing, but being able to make decisions at the same speed under communication disruption during an emergency is another matter. From my experience in the Maritime Self-Defense Force, what is first lacking in actual combat is not the number of vessels but the time to synchronize situational awareness on the same screen.

The Alliance's Blind Spot Lies Outside the Islands

This exercise demonstrates the willingness of Japan and the U.S. to jointly undertake the defense of the first island chain. However, in Okinawa, there is a possibility that resentment towards the burden of bases may reignite following incidents involving U.S. Marines, and the fact that the opening ceremony was closed to the press cannot be overlooked. Deterrence cannot be achieved solely through equipment and training. If local acceptance wavers, the very military premise of dispersed deployment and continuous supply collapses.

According to Tanaka's view, the true test of Keen Sword 2027 is not the accuracy of the Type-25. It is whether a large-scale exercise involving approximately 57,000 personnel can be repeated without losing the understanding of the island residents and without interrupting communication and supply. The next challenge for the Japan-U.S. alliance is not the addition of strike capabilities, but aligning the three decision-making processes of political, military, and local communities on the same timeline.

Main Sources: Mainichi Shimbun / Kyodo News "Major Japan-U.S. joint military drills kick off to boost regional defense" (October 20, 2026), Ministry of Defense / Joint Staff "Japan Self-Defense Forces and U.S. Armed Forces bilateral exercise" materials (October 15, 2026).