Japan and the United States launched the 18th iteration of their biennial Keen Sword 27 military exercise on Monday, October 19, 2026. The 11-day drills involve roughly 56,000 total personnel, featuring Japan’s newly deployed long-range anti-ship missiles and allied forces operating near regional border islands.
The massive joint undertaking kicked off with an opening ceremony on Ishigaki Island, as regional friction involving China, North Korea, and Russia shadows the maneuvers. Running through October 29, the exercise brings together approximately 45,000 Japanese Self-Defense Forces personnel and 12,000 U.S. service members.
Seven other Indo-Pacific and European nations are joining portions of the drills. South Korea and the United Kingdom have sent observers to monitor the operations.
Type-25 Missiles Deployed to Yonaguni Amid Regional Friction
A central focus of this year’s maneuvers is the defense of Japan’s southwestern island chain. Operations stretch across remote outposts, including Tanegashima and Yonaguni, which sits just 110 kilometers (68 miles) east of Taiwan.
Marking a tactical milestone, Japan’s Self-Defense Force introduced its first long-range Type-25 land-to-ship missile to Yonaguni for the exercise. The domestically developed guided missile carries a reported range of approximately 1,000 kilometers (621 miles), though participating units are conducting simulated operations without live firing.
The deployment drew sharp criticism from foreign policy observers. Lü Chao, an East Asian studies expert at the Liaoning Academy of Social Sciences, warned that positioning the weapon system with an emphasis on striking targets along China’s coast constitutes a clear provocation that heightens regional instability.
Today, it is a great privilege and significance to commence Keen Sword 27 in Ishigaki, Japan’s western-most point.
Tawara Tateki, commander of Japan’s Joint Operations Command
U.S. Marine Corps units are concurrently deploying Navy Marine Expeditionary Ship Interdiction Systems (NMESIS) and Mobile Air Defense Integrated Systems (MADIS) across southwestern islands near Taiwan. Live-fire drills are scheduled at a firing range on Oki-Daito, an uninhabited Pacific island roughly 500 kilometers (310 miles) southeast of Okinawa.
USS Theodore Roosevelt Arrives in Yokosuka Under Local Scrutiny
Naval power projections ahead of the drills included the arrival of the aircraft carrier USS Theodore Roosevelt at Yokosuka. The visit marked the first time a non-resident U.S. carrier has docked at the strategic naval port.
The port call coincided with heightened local sensitivities following the recent arrest of an Okinawa-based U.S. Marine linked to the robbery and murder of a Japanese woman. In response to public anger over the crime and broader conduct concerns, Yokosuka Mayor Katsuaki Kamiji requested that Japan’s Foreign Ministry convey to the U.S. military the importance of crew members complying with Japanese rules.
Citizens’ groups and prefectural assembly members voiced additional grievances ahead of the exercises, submitting petitions in locations like Oita to protest Osprey flight paths, potential electromagnetic health effects, and conduct risks tied to stationed American personnel.
Amphibious Landings and Multi-Domain Operations Through October 29
Beyond missile maneuvers, the 11-day schedule integrates complex multi-domain warfare scenarios. Participating forces are executing amphibious landings, air and missile defense maneuvers, mine sweeping operations, intelligence gathering, logistics resupply, and casualty evacuations.
In order to do so, it is essential to be fully prepared and cooperate with our allies and partners to prevent the crisis.
Hiroaki Uchikura, Chief of Staff of the Joint Staff
Diplomatic tensions underpinning the exercises trace back significantly to political statements from the past year. Bilateral ties with Beijing hit strain following Prime Minister Sanae Takaichi’s remarks, a stance that subsequently spilled over into economic friction.
With assets dispersed across northern coasts and southwestern island garrisons through the end of October, military planners maintain that operational readiness remains the primary objective as joint forces navigate an increasingly tense security environment.