Japan, US Launch Keen Sword 27 Drills Near Taiwan with Record Troop Numbers, New Missile Deployments

Japan and the United States began their largest-ever joint military exercise on Monday, focusing on the defense of remote southwestern islands and deploying advanced missile systems near Taiwan, as regional tensions continue to mount.

The biennial Keen Sword 27 drills, running from October 19 to 29, involve approximately 45,000 Japanese Self-Defense Force personnel and 12,000 U.S. service members.

Seven additional nations are participating in parts of the exercise, with France, Germany, the Netherlands, New Zealand, and the Philippines joining for the first time, according to Japan’s Joint Staff.

The drills span multiple locations across Japan, from waters near Hokkaido in the north to the remote islands of Okinawa Prefecture in the southwest.

A key focus of the exercise is Yonaguni Island, Japan’s westernmost territory located just 110 kilometers east of Taiwan.

For the first time, the U.S. military has deployed its Navy-Marine Expeditionary Ship Interdiction System, known as NMESIS, and the Marine Air Defense Integrated System, or MADIS, to the island.

The NMESIS is a ground-based anti-ship missile system with a range exceeding 180 kilometers, while MADIS is designed to intercept low-flying drones and aircraft.

Japan’s Self-Defense Forces have also deployed their new Type-25 surface-to-ship missile system outside its base in Kumamoto Prefecture for the first time.

The missile, which has a range of approximately 1,000 kilometers and is capable of reaching mainland China, was moved to the Ohnobaru training area in Nagasaki and Saga prefectures. No live missile firings are planned during the drills.

Gen. Hiroaki Uchikura, Chief of Staff of Japan’s Joint Staff, denied that the exercises target a specific country.

At an opening ceremony on Ishigaki Island, Japan’s Maritime Self-Defense Force Adm. Tateki Tawara said the goal was to protect peaceful lives. “In order to do so, it is essential to be fully prepared and cooperate with our allies and partners to prevent the crisis,” he said.

The drills have drawn widespread opposition within Japan. Protests have been held in Okinawa, Nagasaki, and Oita prefectures since early October, with demonstrators calling for the exercises to be cancelled and demanding an end to military training at civilian facilities.

Civic groups have warned that the joint exercises will only heighten regional tensions and put local residents at risk.

Local concerns have also been heightened by the recent arrest of a U.S. Marine in connection with the murder and robbery of a Japanese woman on Okinawa, where the majority of the approximately 50,000 American troops stationed in Japan are based.

The case has renewed anti-base sentiment on the island, where residents have long complained about noise, pollution, and crime linked to U.S. military presence.

The exercise comes amid strained Japan-China relations following Prime Minister Sanae Takaichi’s remark a year ago that Chinese military action on Taiwan could justify Japanese involvement.

Japan has also raised concerns over China’s increased military activity around remote Japanese islands in the Pacific Ocean.

Keen Sword is held every two years and is one of the largest bilateral field training exercises between the two allies.

This year’s drills also include training in new domains such as space, cyberspace, and electromagnetic warfare, alongside traditional amphibious landing, missile defense, and casualty evacuation exercises.