Japan Self-Defense Forces Deploy Type 25 Anti-Ship Guided Missile for the First Time, Keen Sword 2026 Operationalizes Japan-U.S. Southwest Defense

On October 19, the Japan-U.S. joint integrated exercise "Keen Sword 26," which began at the Ground Self-Defense Force's Ishigaki garrison, has gone beyond the realm of a mere routine exercise. This exercise, which includes land, sea, air, as well as space and cyber domains, involves approximately 45,000 Self-Defense Forces personnel and about 12,000 U.S. military personnel, totaling over 50,000 participants. Operations are scheduled to continue until October 29 in the southwestern and northern air and maritime areas of the Japanese archipelago.

What the Initial Deployment of the Type 25 Indicates

The focus this time is on the operational use of the Type 25 anti-ship guided missile, which was deployed in March. The missile, launched from a vehicle-mounted launcher, has an estimated range of about 1,000 kilometers, and the Ground Self-Defense Force has moved four related vehicles from the Kumamoto Ken-gun garrison to the Ōyanohara training area on the Nagasaki-Saga prefectural border. The exercise will simulate a series of procedures from target detection to firing.

Ishigaki Island is located about 270 kilometers from Taiwan. The significance of incorporating long-range anti-ship firepower here is not just to defend the islands. It is about distributing denial capabilities that do not solely rely on aircraft and escort ships against vessels approaching sea lines of communication (SLOC). However, even if the missile's range is extended, if there is no accompanying update of target information, launch authorization, resupply, and communication survivability, the capability will remain just a number.

Integration of Alliances and Political Friction

Seven countries, including France and Germany, are participating, with five of them being first-time participants. This is an attempt to expand Japan-U.S. bilateral island defense to information sharing and logistical support with allied nations. The message from the Ministry of Defense's Joint Staff Office, "We will not allow unilateral changes to the status quo by force," can also be understood as a combination of showcasing capabilities and deterrence.

On the other hand, in Okinawa, a few weeks before the exercise began, a U.S. Marine was arrested on suspicion of murder and robbery. Reports suggest that the background to the ceremony in Ishigaki not being open to the press was also due to consideration for local residents' feelings. The more deterrence is strengthened, the more difficult it becomes to politically adjust with regions bearing the burden of bases, which is an internal issue within the alliance.

Speed Over Capability is Being Tested

According to Tanaka's assessment, the core of Keen Sword 26 is not the range of the Type 25, but how quickly the Japan-U.S. command systems can connect from detection to firing. The "capabilities" aimed at China and North Korea are being developed. However, what is needed in the initial stages of a crisis is not the enhancement of equipment lists, but the speed at which target information, political decisions, and resupply can be moved simultaneously. The blind spot in the defense of the southwestern islands is not the distance beyond the missile's reach, but the time it takes for decisions to be made.

Sources

• Ministry of Defense, Joint Staff Office "Japan-U.S. Joint Integrated Exercise" Press Release (October 15, 2026)
• Mainichi Shimbun/Kyodo "Major Japan-U.S. joint military drills kick off to boost regional defense" (October 20, 2026)
• The Washington Post "Japan and the U.S. kick off joint drills around islands as regional tensions rise" (October 19, 2026)