Japan will deploy medium-range surface-to-air missiles on its remote western island of Yonaguni Island by March 2031, Defence Minister Shinjiro Koizumi announced on Tuesday, marking the first time Tokyo has specified a timeline since the plan was unveiled in 2022.
The move comes amid heightened regional tensions, driven largely by China’s growing pressure on Taiwan, which Beijing claims as its territory and has not ruled out taking by force.
Yonaguni — Japan’s westernmost inhabited island — lies just 110 km from Taiwan, close enough to be visible on a clear day.
Rising tensions between Japan and China
Relations between Tokyo and Beijing have been strained since November, when Japanese Prime Minister Sanae Takaichi suggested that Japan could activate its Self-Defense Forces if Taiwan were attacked.
China denounced her remarks, calling them “provocative,” triggering the sharpest downturn in bilateral ties in years.
Beijing has since responded with a series of pressure tactics, including:
- Deploying warships near Japan
- Limiting rare earth exports
- Restricting Chinese tourism to Japan
- Cancelling cultural events and concerts
- Reclaiming its pandas from Japanese zoos
China also flew military drones near Yonaguni shortly after Koizumi’s November visit, prompting Japan to scramble fighter jets.
What Japan’s new missile unit will look like
Koizumi said the Yonaguni unit will deploy Japanese-made medium-range SAMs, designed to intercept:
- Incoming aircraft
- Cruise missiles
- Potential unmanned aerial threats
Key capabilities include:
- 50 km range
- 360-degree coverage
- Ability to track up to 100 targets simultaneously
- Ability to engage 12 targets at once
The missile installation is part of Tokyo’s broader plan to fortify its southwestern island chain — a region seen as the front line in any conflict involving Taiwan.
A strategically transformed island
Over the past decade, Tokyo has rapidly expanded Yonaguni’s military profile.
Once a quiet outpost, the island now hosts 160 Self-Defense Force personnel and serves as a hub for:
- Coastal surveillance operations
- Maritime monitoring
- Intelligence gathering
In fiscal year 2026 (April 2026–March 2027), Japan will add an electronic warfare unit capable of disrupting enemy communications and radar — further solidifying the island’s role as a forward-deployment base.
Koizumi said the missile timeline may shift depending on construction progress, but the current target is fiscal year 2030, which ends in March 2031.
A more assertive Tokyo under Takaichi
Prime Minister Takaichi’s landslide election victory earlier this month has given her political room to accelerate Japan’s defense build-up.
Her administration is pushing for:
- Expanded military capabilities
- A larger defense budget
- A hardline stance against Chinese pressure
- Closer security alignment with the United States
Analysts say the Yonaguni missile announcement reflects Japan’s clearest signal yet of how far it is prepared to go to defend its territory and support Taiwan in the event of conflict.
This marks the opening chapter of a more assertive Japanese security posture, one unlikely to soften anytime soon.