US Marine Corps anti-ship weaponry to see exercise action on remote Japan island near Taiwan

MANILA, Philippines — The U.S. Marine Corps will deploy its ground-based anti-ship and air-defense systems to Japan’s southwesternmost island for exercise Keen Sword, placing new U.S.-Japan capabilities on an island sitting just 110 kilometers from Taiwan.

Keen Sword, the largest U.S.-Japan biennial joint drill, will feature two key systems of the Marine Corps’ littoral force: the anti-ship NMESI S (Navy-Marine Expeditionary Ship Interdiction System) and air-defense MADIS (Marine Air Defense Integrated System).

Yonaguni’s local government disclosed the deployment on Friday, a day after the Okinawa Defense Bureau relayed deployment plans on Oct. 1.

The systems will be deployed to Yonaguni for the first time, as this year’s iteration shifts to ground-based, multi-island, sea-denial operations aimed at distributing American and Japanese forces across the southwestern islands.

The deployment also reflects a broader shift by the United States and Japan toward mobile missile and air-defense systems that can operate from scattered islands .

NMESIS and MADIS form the cornerstone of the U.S. Marine Corps’ force design modernization and restructuring plan, which moves away from heavy armored platforms to focus on small-unit, expeditionary forces that can capture and defend islands.

NMESIS can strike targets at around 115 miles and could threaten ships operating in waters around Taiwan. The reported deployment, in turn, has drawn criticism from Chinese military experts even while China’s PLA Navy and coast guard vessels have increased activities around Taiwan.

The NMESIS and MADIS systems first arrived with the Okinawa-based 12th Marine Littoral Regiment 3rd Marine Division in June. The units were earlier deployed to the Philippines’ northern Batanes Islands and western Laoag province during the Balikatan drills.

The deployment comes as Japan tests what defense officials describe as standoff-strike capabilities, missile systems that can strike targets far from enemy weapons, while strengthening its southwestern islands for distributed military operations.

According to the Ministry of Defense, troops from nine countries, including the Australian and French armies, will join 45,000 Japanese Self-Defense Forces personnel for this year’s exercise, which will run from Oct. 19 to 29.

The exercise will also bring together a number of U.S. and Japanese ground-based missile systems.

The U.S. Army will deploy HIMARS (High Mobility Artillery Rocket Systems) weapons to Camp Ishigaki, some 80 miles from Yonaguni.

The Army’s Typhon missile launcher will also be moved to Okinawa mid-month, although no disclosures have been made about whether the mid-range system will be used for the exercise.

In past iterations of the drill, the USS George Washington joined the exercises, but the carrier strike group was sent to the Arabian Sea in August to replace the USS Abraham Lincoln, which was returning home after a prolonged deployment.

That prominent naval absence is expected to emphasize the exercise scenario shift toward a land-based network of mobile systems.

Last year, exercises in Yonaguni focused on maximizing the island as a forward operating base. This year, Keen Sword will showcase the Ground Self-Defense Force’s three anti-ship missile systems, which are the core of Japan’s long-range standoff-strike capabilities.

The JGSDF will train with the new ground-launched Type-25 surface-to-ship guided missile system, formerly known as the upgraded Type-12, which was fielded across the Nansei Islands in late March. The Type-25 SSM has a strike reach of 1,000 kilometers.

The lineup also includes the Type-88 ground-to-ship missile and the upgraded Type 03 Chu-SAM Kai medium-range ground-to-air guided missile.

Keen Sword was originally planned as a much larger exercise, local government officials said, but opposition forced the ministry to scale it down to its current iteration.

Yonaguni is Japan’s last inhabited island in the Nansei, a chain of scattered islands in southwestern Okinawa and a fast-emerging flashpoint amid rising tensions around Taiwan.

The JGSDF set up a radar and surveillance system on the island in 2016 to fill a “surveillance vacuum” in the seascapes stretching from the island to Taiwan, according to officials.

The island has seen increased joint exercises between Japanese and U.S. troops while it faces incursions from Chinese ships.

In June this year, the government reported incursions by Chinese Coast Guard ships encroaching on Japan’s exclusive economic zone between Yonaguni and Taiwan. In 2022, China’s ballistic missile landed just 80 kilometers from the island.

While tensions surround the island, local officials have raised concerns about the use of civilian roads, ports, and airways.

Large equipment for the exercise will be transported by sea through Kubura Port, and local authorities have asked residents to avoid using roads during the movement of military equipment.

There are also concerns after a Japan Self-Defense Forces V-22 Osprey was involved in a ground-strike incident in the same exercise in 2024. The incident prompted then-defense minister Gen Nakatani to order the grounding of Japan’s 17 Osprey aircraft.

This year, however, the V-22 Osprey will not participate, Yonaguni Mayor Tsuneo Uechi told Mainichi Shimbun on Oct. 2.

While the island understands the need for military training, Uechi said it is not ready for large-scale exercises that exceed the island’s capacity. The local government remains opposed to the exercises and continues to hold talks with the defense ministry.

Leilani Chavez is an Asia correspondent for Defense News. Her reporting expertise is in East Asian politics, development projects, environmental issues and security.

菲律宾马尼拉——美国海军陆战队将在日本最西南端的岛屿上部署其陆基反舰和防空系统，参加“利剑”演习，将新的美日联合作战能力部署到距离台湾仅 110 公里的岛屿上。

“利剑”是美日两国规模最大的两年一度联合演习，将重点展示海军陆战队近岸部队的两大关键系统：反舰系统 NMESI S（海军陆战队远征舰艇拦截系统）和防空系统 MADIS（海军陆战队防空综合系统）。

与那国岛地方政府于周五公布了部署计划，此前一天，冲绳防卫局于 10 月 1 日公布了部署计划。

该系统将首次部署到与那国岛，因为今年的演习转向了以地面为基础的多岛海上拒止作战，旨在将美日军队分散到西南诸岛。

此次部署也反映出美国和日本正在向可从分散岛屿上作战的移动式导弹和防空系统进行更广泛的转变。

NMESIS 和 MADIS 构成了美国海军陆战队部队设计现代化和重组计划的基石，该计划旨在摆脱重型装甲平台，转而专注于能够占领和保卫岛屿的小型远征部队。

NMESIS导弹射程可达约115英里，可能对在台湾附近海域活动的船只构成威胁。据报道，NMESIS导弹的部署引发了中国军事专家的批评，与此同时，中国人民解放军海军和海警舰艇在台湾附近海域的活动也日益频繁。

NMESIS和MADIS系统于6月率先交付给驻扎在冲绳的第3海军陆战师第12近海团。此前，这些部队曾在“肩并肩”联合军演期间部署到菲律宾北部的巴丹群岛和西部的老沃省。

此次部署正值日本测试其国防官员所称的防区外打击能力之际，这种导弹系统能够打击远离敌方武器的目标，同时加强其西南岛屿的防御能力，以开展分散式军事行动。

据日本防卫省称，包括澳大利亚和法国军队在内的九个国家的军队将与45000名日本自卫队人员一起参加今年的演习，演习将于10月19日至29日举行。

此次演习还将汇集美国和日本的多套陆基导弹系统。

美国陆军将向距离与那国岛约 80 英里的石垣营地部署 HIMARS（高机动性火箭炮系统）武器。

陆军的“台风”导弹发射器也将于本月中旬移至冲绳，但尚未透露该中程导弹系统是否会用于此次演习。

在以往的演习中，“乔治·华盛顿”号航空母舰也曾参与演习，但该航母打击群于 8 月被派往阿拉伯海，以替换在长期部署后返回母港的“亚伯拉罕·林肯”号航空母舰。

海军的明显缺席预计将凸显演习场景向陆基移动系统网络的转变。

去年，与那国岛的演习重点在于最大限度地发挥该岛作为前沿作战基地的作用。今年的“利剑”演习将展示日本陆上自卫队的三套反舰导弹系统，它们是日本远程防区外打击能力的核心。

日本陆上自卫队将使用新型陆基25型舰对舰导弹系统进行训练。该系统前身为升级版12型舰对舰导弹，已于3月下旬在南西列岛部署。25型舰对舰导弹的打击范围为1000公里。

该系列导弹还包括 88 式地对舰导弹和升级后的 03 式 Chu-SAM Kai 中程地对空导弹。

当地政府官员表示，“利剑”演习最初计划规模更大，但由于反对，演习规模被迫缩减为目前的版本。

与那国岛是日本南西群岛中最后一个有人居住的岛屿，南西群岛位于冲绳西南部，由一系列分散的岛屿组成，随着台湾周边地区紧张局势的加剧，南西群岛正迅速成为一个新兴的冲突爆发点。

据官方消息，日本陆上自卫队于 2016 年在该岛设立了雷达和监视系统，以填补从该岛延伸至台湾海域的“监视真空”。

该岛近期加强了日美军队的联合演习，同时还面临着中国船只的入侵。

今年6月，日本政府报告称，中国海警船侵入了与那国岛和台湾之间的日本专属经济区。2022年，中国的一枚弹道导弹落在距离该岛仅80公里的地方。

尽管岛上局势紧张，但当地官员对民用道路、港口和航空道的使用表示担忧。

演习所需的大型装备将通过久保良港海运，当地政府已要求居民在军事装备运输期间避免使用道路。

此外，2024 年日本自卫队的一架 V-22“鱼鹰”倾转旋翼机在同一演习中发生对地攻击事件，也引发了人们的担忧。该事件促使当时的防卫大臣中谷元下令停飞日本的 17 架“鱼鹰”倾转旋翼机。

但今年 V-22 鱼鹰将不会参加，与那国市市长上地恒夫于 10 月 2 日告诉《每日新闻》。

虽然该岛理解军事训练的必要性，但上地表示，该岛尚未做好应对超出自身承受能力的大规模演习的准备。当地政府仍然反对此次演习，并继续与国防部进行磋商。

莱拉尼·查韦斯是《防务新闻》的亚洲记者。她的报道专长是东亚政治、发展项目、环境问题和安全。