What happened
The US and Japan have launched a large-scale military exercise, known as Keen Sword 27, involving approximately 57,000 Japanese and American personnel. The 11-day exercise, which started on October 19, includes about 45,000 Japanese and 12,000 US personnel, along with around 45 ships and 380 aircraft from the two countries.
Seven other countries, including Australia, Canada, France, Germany, the Netherlands, New Zealand, and the Philippines, are also participating in the exercise, while South Korea and the UK are attending as observers. The exercise aims to practice missile deployments and joint operations near Taiwan, and will test the two militaries' ability to move, supply, and coordinate forces across geographically separated islands.
The exercise will also involve anti-ship combat, missile defense, amphibious operations, cybersecurity, and military activities involving space and electromagnetic systems. A significant part of the exercise will take place across Japan's southwestern islands, which extend toward Taiwan, with the US Marine Corps planning to deploy its Navy-Marine Expeditionary Ship Interdiction System (NMESIS) and Marine Air Defense Integrated System (MADIS) to Yonaguni, Japan's westernmost inhabited island.
The exercise comes as Tokyo faces increased Chinese military activity around the Japanese islands and Taiwan, with Japan's 2026 Defense White Paper identifying China's expanding military activities as an unprecedented and major strategic challenge. The exercise is not directed at any particular country or region, but rather aims to strengthen the US-Japan alliance's ability to respond to security challenges.
