Japan to deploy air defense missiles on Yonaguni near Taiwan as China warns of rising tensions

Why Yonaguni matters now

Japan is moving ahead with plans to place a surface to air missile unit on Yonaguni, a small island only about 110 kilometers east of Taiwan. The step comes after a recent scramble by Japanese fighter jets to intercept a suspected Chinese drone flying between Yonaguni and Taiwan, a corridor that would be crucial in any crisis over the Taiwan Strait. Tokyo says the deployment is defensive. Beijing calls it dangerous. The argument captures how a tiny island has become central to security planning in East Asia.

Yonaguni has roughly 1,700 residents, two small ports and a short airfield. It already hosts a Self Defense Forces radar site that scans nearby seas and skies, plus an electronic warfare unit stood up in 2024. The United States Marine Corps has set up a forward arming and refueling point on the island, giving American aircraft a place to top up close to the strait. Yonaguni sits at the western end of the Ryukyu archipelago, which stretches northeast toward Okinawa and Kyushu. This arc is part of what strategists call the first island chain. Control of that chain, or even the ability to deny control to an adversary, shapes any plan to coerce or defend Taiwan.

What Japan plans to place on the island

Defense Minister Shinjiro Koizumi visited Yonaguni and said the deployment would proceed. He described the move as a way to strengthen deterrence rather than raise the risk of conflict.

Introducing his position during the visit, the minister set out Tokyo’s rationale. He said:

The deployment can help lower the chance of an armed attack on our country. The view that it will heighten regional tensions is not accurate.

The unit planned for Yonaguni is the Type 03 Chu SAM, a domestically designed, medium range surface to air missile system. The battery is mobile, with launchers mounted on 8×8 trucks. Its radar uses a phased array to track many targets at once. The system can engage multiple aircraft, helicopters, and cruise missiles at ranges up to roughly 48 kilometers, with intercepts at medium altitude. It is made to be moved, set up, fired, and then relocated to reduce vulnerability.

Japan integrates the Type 03 into a broader air and missile defense network that includes Patriot PAC 3 batteries on land and Aegis destroyers at sea with SM 3 interceptors and, in the future, SM 6. Yonaguni already contributes radar data to this network. A new battery there would act as a forward node, providing point defense for the island and supporting the picture of air activity in the channel between Taiwan and the Ryukyus.

What the missiles can and cannot do

The Type 03 cannot threaten targets on Taiwan or on the Chinese mainland. Its value is local. It can cover the airspace immediately around Yonaguni and the sea lane to the island’s east and south. That coverage complicates the job of any pilot, drone operator, or cruise missile planner trying to operate close to the island. It can also protect other assets that might be placed on the island in a crisis, such as sensors or mobile launchers for anti ship and long range weapons. Combined with other Japanese and American systems, it adds another layer that adversaries must account for.

China responds and a sharper diplomatic chill

China’s government has condemned the plan. Officials argue that placing missiles so close to Taiwan invites confrontation. The rhetoric has sharpened amid a broader downturn in ties after Japanese Prime Minister Sanae Takaichi said that a Chinese military blockade of Taiwan could meet the constitutional threshold of a survival threatening situation, which would allow collective defense with the United States.

At a regular press briefing, Chinese Ministry of Foreign Affairs spokesperson Mao Ning criticized the move in strong terms. She said:

Japan’s deployment of offensive weapons to southwest islands close to China’s Taiwan is a deliberate move that creates regional tensions and stokes military rivalry. Given Prime Minister Takaichi’s erroneous remarks on Taiwan, this move is extremely dangerous. Neighboring countries and the world should be on high alert.

Chinese state media voices have accused Tokyo of reviving militarism. The tone underscores how sensitive military moves have become around the strait. A Chinese company even posted a video that simulated strikes on Japanese targets with a new hypersonic missile, an example of heated messaging in the information space.

Japan, for its part, says the plan is consistent with its constitution and with its publicly stated focus on defending its territory. Tokyo has spent the past decade updating security laws to allow limited collective self defense, while still describing its posture as defensive. On paper, the Yonaguni battery is meant to make an attack on Japanese soil less likely, not more likely.

How Taiwan and the United States view the move

Officials in Taipei have welcomed stronger defenses on nearby Japanese islands. They view them as a contribution to stability in the strait. Taiwan’s Deputy Minister of Foreign Affairs Francois Wu put it plainly when asked about the plan. He said Japan has the right to safeguard its territory and that steps on Yonaguni can help maintain security in the Taiwan Strait, which he said aligns with Taiwan’s interests.

For the United States, Yonaguni fits into a wider strategy that relies on the first island chain. American Marines have practiced moving supplies from Okinawa to Yonaguni to simulate building a forward base in a crisis. Washington is also helping Taiwan tighten its defenses, including approval of National Advanced Surface to Air Missile Systems and other support such as aircraft parts. Across Japan, American units have brought in mobile launchers that could be positioned closer to Taiwan if a crisis emerged. These include systems like Typhon, which can fire SM 6 surface to air and Tomahawk land attack missiles, and High Mobility Artillery Rocket Systems used for long range precision fires. The Navy Marine Expeditionary Ship Interdiction System, which fires the Naval Strike Missile, could also find value on islands that overlook Chinese sea routes.

None of this guarantees a smooth defense in wartime. China has invested in surveillance, electronic warfare, and a large inventory of ballistic and cruise missiles to keep foreign forces at a distance. Even so, each additional radar site, mobile missile unit, and logistics hub gives the United States and Japan more options to contest the air and sea around Taiwan.

Life on Yonaguni and local concerns

The debate is not just strategic. It is personal for people living on the island. Yonaguni’s mayor has asked Tokyo to help fund air raid shelters so residents have protection if a crisis erupts. The defense ministry says it will brief local officials and residents once plans are finalized. Contingency planning discussed by officials includes evacuating people to Kyushu if there is time, as well as building underground shelters across the southwest islands that can support those who cannot leave for up to two weeks. Yonaguni is also a tourist destination, known for clear waters and scuba diving sites. Residents want safety without losing the character of their community.

The island has already felt nearby military activity. In 2022, when China held large exercises around Taiwan after a high profile visit from a senior American lawmaker, several ballistic missiles splashed down near Yonaguni. The event underlined how closely the island is tied to any confrontation around Taiwan. That experience helped drive civil defense planning across the Ryukyus, with local governments considering drills, siren systems, and reinforced facilities.

What a Taiwan crisis could mean for the island

If tensions over Taiwan turn into a standoff or a shooting war, the waters and airspace between Taiwan’s east coast and the Ryukyus would become contested quickly. Yonaguni’s radar and any air defense unit on the island would feed early warning to Japan and the United States. The Type 03 battery could defend the island against low flying aircraft and cruise missiles for a period, especially if operators keep it hidden, move frequently, and use decoys to mislead enemy sensors.

Survivability would be a challenge. China has many ways to strike fixed points, including ballistic missiles, land attack cruise missiles, and long range drones. The Type 03 is not optimized for intercepting ballistic missiles, so layered defenses matter. Patriot PAC 3 and Aegis ships would shoulder more of that task, while the Type 03 would focus on aircraft and cruise missiles. Even then, the volume of fire an adversary can generate could overwhelm a single battery. In a crisis, the answer is dispersion and integration. Many small, mobile units sharing data can be harder to neutralize than a few large, static targets.

The wider military picture across the first island chain

Yonaguni is one piece of a larger map. Japan has spent years adding units across the Nansei islands. Ishigaki hosts anti ship missiles that look out on shipping lanes south of Okinawa. Miyako has become a hub for air surveillance and ammunition storage. Okinawa, further east, remains home to major Japanese and American bases. Tokyo has boosted defense budgets and is pursuing counterstrike capabilities, arguing that it must be able to disrupt attacks aimed at its territory.

The United States and Japan are also testing new ways to operate in a more dangerous environment. Marines and soldiers are practicing small unit deployments to austere islands and logistics under threat. Sensors on land, at sea, and in the air are being tied together to create a common operating picture. Long range missiles like SM 6 and Tomahawk on land based launchers, and Naval Strike Missiles in mobile shore batteries, offer the promise of complicating Chinese fleet movements. Even if these systems are not placed on Yonaguni in peacetime, they could be surged to the southwest islands in an emergency.

Deterrence, escalation, and what comes next

The strategic logic behind placing a Type 03 unit on Yonaguni is deterrence by denial. Japan wants a would be aggressor to see that any attempt to operate near the island will face risk. That logic has a tradeoff. Forward positions also become targets in any exchange, and Beijing is already treating the plan as a provocation. Managing this tension will require clear communication among governments, reliable crisis channels, and training that reduces the chance of miscalculation.

Geography cannot be wished away. Yonaguni sits near the routes that matter most in a Taiwan crisis. That is why the island is drawing missiles, sensors, and attention. Tokyo and its partners aim to show that preparing defenses reduces the chance of a fight, even as they work to keep pressure from boiling over.

What to Know

• Japan will deploy a Type 03 Chu SAM air defense unit on Yonaguni, about 110 kilometers east of Taiwan.
• Defense Minister Shinjiro Koizumi says the deployment lowers the chance of an attack on Japan and is not meant to inflame tensions.
• China’s Foreign Ministry calls the plan extremely dangerous and accuses Japan of creating regional tension.
• Taiwan’s Deputy Foreign Minister Francois Wu says stronger defenses on nearby Japanese islands help maintain security in the strait.
• Yonaguni already hosts a radar site and an electronic warfare unit, and the United States Marines have set up a forward arming and refueling point there.
• The Type 03 can engage aircraft and cruise missiles out to roughly 48 kilometers but is designed for local defense, not strikes on distant targets.
• Japan’s air and missile defense network also includes Patriot PAC 3 batteries and Aegis destroyers with SM 3 and SM 6 interceptors.
• In a crisis, Yonaguni could be targeted by Chinese missiles and drones, making mobility, concealment, and layered defenses essential.
• Japan is strengthening other southwest islands with anti ship missiles and surveillance hubs, while the United States rehearses logistics and mobile deployments in the region.
• Officials are planning civil defense measures on Yonaguni, including shelters and potential evacuation to Kyushu if time allows.