US and Japan Rehearse Anti-Ship Strikes Near Taiwan in Keen Sword 27

The exercises mark a measurable escalation in allied military coordination against specific naval scenarios, signaling that Washington and Tokyo are preparing operational responses to potential...

United States and Japanese forces have conducted coordinated anti-ship strike rehearsals and mobile missile deployments across Kyushu and Japan's southwestern island chain during the ongoing Keen Sword 27 exercise, according to reporting by the South China Morning Post. The drills are specifically designed to test tactics that would challenge the People's Liberation Army Navy's ability to dominate the waters surrounding Taiwan in a conflict scenario.

Keen Sword 27 entered its second week as of the date of this report, with the full exercise spanning 11 days. According to the South China Morning Post, the allied forces have tested how they could threaten Chinese naval vessels from multiple directions while maintaining dispersed, mobile positions to reduce their own vulnerability to counterstrikes.

The exercise takes place across Kyushu, Japan's southernmost main island, and the Nansei Islands, also known as the Ryukyu chain, which extends southwestward toward Taiwan. This geography is significant: the Nansei Islands sit directly along the maritime corridor that any Chinese naval operation targeting Taiwan would likely need to traverse or control.

Mobile missile deployments were a central feature of the rehearsals. Ground-based anti-ship missile systems, when dispersed across multiple islands, present a networked threat to adversary surface fleets that is more difficult to neutralize than fixed installations. This approach reflects a broader shift in US and Japanese defense planning toward distributed lethality, a concept documented in US Indo-Pacific Command strategy papers.

Japan has significantly expanded its defense posture in recent years. The Japanese government's December 2022 National Security Strategy authorized the acquisition of counterstrike capabilities, a departure from Japan's postwar defense policy that had restricted the Self-Defense Forces to purely defensive operations. That policy shift created the legal and budgetary framework for Japan to participate in the kind of offensive strike rehearsals described in the Keen Sword 27 reporting.

Taiwan's status remains one of the most closely watched geopolitical fault lines in the Indo-Pacific. The People's Republic of China regards Taiwan as a province to be reunified with the mainland and has not ruled out the use of force. The United States maintains a policy of strategic ambiguity, supplying Taiwan with defensive arms under the Taiwan Relations Act of 1979 while not explicitly committing to military intervention.

The PLA has conducted its own large-scale exercises near Taiwan in recent years. In August 2022, following a visit to Taipei by then-House Speaker Nancy Pelosi, the PLA staged encirclement drills that simulated a blockade. Further exercises followed in 2023 and 2024. Each round of Chinese drills has been met with US calls for restraint while allied forces have simultaneously increased their own exercise tempo in the region.

Keen Sword is a recurring bilateral exercise between US and Japanese forces held roughly every two years. The 2024 iteration, Keen Sword 25, also incorporated island-defense scenarios, but the 2026 version's explicit focus on coordinated anti-ship fires from dispersed island positions represents a more operationally specific scenario, according to the South China Morning Post report.

China's Ministry of National Defense had not issued a formal public response to the Keen Sword 27 exercises as of the publication of this report. Beijing has previously characterized similar allied drills as destabilizing and has called on the United States to stop what it describes as interference in China's internal affairs regarding Taiwan.

What remains publicly unknown is the full order of battle for the exercise, including the specific missile systems deployed and the precise units participating. Those details, if released, would provide a clearer picture of how far operational planning between US and Japanese forces has advanced toward a Taiwan contingency.