U.S. and Japan Stage Coastal-Defense Drills Near Taiwan, Showcasing Advanced NMESIS Missile System

The United States and Japan have launched a new round of joint military exercises that will put some of their most advanced coastal-defense weapons on display at a strategically sensitive location near Taiwan, underscoring allied efforts to deter China’s expanding military reach.

The drills began Monday and include deploying the U.S. Marine Corps’ Navy-Marine Expeditionary Ship Interdiction System, or NMESIS, to Yonaguni Island, a Japanese outpost in Okinawa Prefecture that sits close to Taiwan. Yonaguni’s geography places it along key sea lanes in the East China Sea and the wider waters connecting Japan, Taiwan, and the Philippines—areas that have become focal points of regional security planning as Beijing boosts naval and air activity.

NMESIS is a land-based missile system intended for coastal defense. It is designed to target hostile ships and reduce their ability to operate near shorelines, effectively creating a denial zone that can make it riskier for adversary vessels to approach or maneuver close to an island chain. By practicing with the system on Yonaguni, the allies are demonstrating how they might reinforce front-line islands and complicate any attempted maritime advance.

The exercises come amid heightened concern in Washington and Tokyo about China’s growing military capabilities and its increasing pressure in waters and airspace around Taiwan and Japan’s southwestern islands. Japan has been strengthening defenses in this region for years, in part because any conflict involving Taiwan could quickly spill into nearby Japanese territory and sea routes vital to the country’s economy.

While the announcement focuses on the start of the drills and the deployment of NMESIS, the broader message is one of interoperability: the U.S. and Japan continue to integrate how they operate in contested environments, especially around islands that could play an outsized role in shaping access to the first island chain. For Japan, that means preparing to host and coordinate with U.S. forces and systems; for the United States, it means working from dispersed locations to maintain maritime control and support regional allies.

The joint training also serves as a signal—both to domestic audiences and to regional partners—that the two countries are investing in practical deterrence measures, not only high-level statements. As China expands its naval power and modernizes its missile forces, the placement of advanced launchers on an island so close to Taiwan highlights how quickly the security landscape is changing around the western Pacific’s most contested flashpoints.

Why it matters

For communities and businesses across Japan and the broader region, stability around Taiwan and nearby sea lanes affects trade, energy supplies, and long-term investment risk. The drills show the U.S. and Japan are prioritizing coastal-defense capabilities on the front line, a move likely to influence China’s calculus and regional defense planning. Watch next for whether deployments and training in Japan’s southwest become more frequent or more permanent—and how Beijing responds diplomatically and militarily.