Japanese Prime Minister Fumio Kishida visited Kiev in late March 2023. Photo: AFP / Masanori Genko / The Yomiuri Shimbun

This past weekend, Nikkei Asia published several satellite images of a military site in Xinjiang with what appears to be a full-scale model of the E-767, Japan’s early-warning aircraft that carries advanced radars for detecting missiles and aircraft at large distances. 

The People’s Liberation Army has constructed replicas of US warships and bases in the past, and recently created a target resembling a Taiwanese naval base. However, these images are particularly revealing. They demonstrate the PLA’s intentions to disable Japan’s airborne early-warning system, a clear sign that the Communist Party of China intends to strike Japan first, and hit it hard, if a conflict begins.

Considering the shifts that Russia’s invasion of Ukraine has caused to the Eurasian political balance, it is essential for the US to maximize Japan’s utility to an anti-China coalition. The single most consequential step the US could take would be to integrate Taiwanese and Japanese defense planning, thus leveraging Japanese forces during a Pacific war.

Prior to the publication of these images, Japan was a likely target during the early phases of a cross-Strait conflict. Strategic factors make Japanese involvement in a cross-Strait conflict highly likely, assuming – as is currently the case – that Japan is not a Chinese satellite. 

Just as a unified, hostile Korea, or Korea under hostile control, would be a dagger aimed at the Japanese home islands, a Taiwan under hostile control would pose a threat to Japan’s exposed Pacific-facing coastline.

Moreover, there are clear cultural and historical affinities between Taiwan and Japan. Japan did colonize Taiwan between 1895 and 1945. But once the Taiwanese insurgency was broken in the 1910s, Japan emphasized integrating Taiwan into a Japanese cultural sphere, expanding Taiwanese infrastructure, and creating the modern Taiwanese university system – National Taiwan University, the country’s foremost higher educational institution, was founded as one of Japan’s nine imperial universities. 

Now, while Japan remains unpopular in Korea and mainland China, the Taiwanese population retains a favorable view of Japan and Japanese culture. More recently, Japan’s donation of 1.24 million Covid-19 vaccine doses last June, just as Taiwan experienced its first major outbreak, reinforced Japanese-Taiwanese amity.

These strategic and historical motivations have prompted an increasingly forward-leading Japanese foreign policy. Japan’s most recent Diplomatic Bluebook mentions Taiwan four times. Its 2021 Defense of Japan White Paper identified Taiwanese security as a crucial strategic concern. 

Last summer, Japanese elder statesmen Taro Aso, then deputy prime minister, stated that Japan would consider an attack on Taiwan a “survival-threatening situation.” By implication, this would obviate the Japanese constitution’s non-aggression clauses, and enable combat deployment by the Japan Self-Defense Forces (JSDF) .  

Although Taro Aso – along with longtime prime minister Shinzo Abe and his successor Yoshihide Suga – are no longer in government, the new prime minister, Fumio Kishida, has continued Japan’s tilt against China. 

Kishida was deemed a dovish liberal upon his election in 2021, considering his restrained stance toward China as foreign minister, his appointment of moderate Yoshimasa Hayashi as foreign minister, and his quiet yet persistent discomfort with modifying the Japanese constitution. Initially, the Kishida government balanced American and Chinese security concerns, despite improving defense cooperation with the United States.

The Russo-Ukrainian War has prompted a sea change in Japanese foreign policy. The Kishida government has placed sanctions on Russia and coordinated closely with the European Union over its response to the February 24 invasion. 

In its defense policy proposals, Kishida’s Liberal Democratic Party recommended increasing the defense budget and, most critically, developing “counterattack” capabilities that can target missile launchers and command and control nodes – that is, offensive capabilities that Japan has not fielded since 1945. During his summit with US President Joe Biden this Monday, Kishida also pledged to increase defense spending.

Japan has been a valuable US ally since the Cold War began. It provides the US with basing access in the Western Pacific and is an ideal location for prepositioned weapons stocks. During the later Cold War, the US leveraged Japanese military power: Japan became responsible for anti-submarine operations in the Philippine Sea, freeing up US assets to pressure the Soviet naval bastion in the Sea of Okhotsk. 

American, Japanese, and other allied warships, aircraft and submarines consistently exercise together. Japan is a founding member of the Quadrilateral Security Dialogue, the diplomatic pact that, along with AUKUS, will undergird an Indo-Pacific anti-China coalition. Moreover, Japan may join AUKUS, if Japanese media reports from last month are to be believed.

Japan is the world’s third-largest economy. In total tonnage, it has the world’s fourth-largest navy. The JSDF has 247,150 men and women under arms. On paper, therefore, it should be a major contributor to an anti-Chinese Indo-Pacific defense structure.

The Japan Maritime Self-Defense Force (JMSDF) – Japan’s de facto navy – is the JSDF’s most capable element. It fields 22 submarines, including 11 ultra-quiet Soryu-class attack submarines, multiple anti-air and anti-submarine surface combatants, and after the Izumo-class conversion, will operate two light aircraft carriers. 

The JASDF operates the F-15 fighter aircraft, a variant of the F-16, and the F-35. It is one of six militaries in the world to operate the E-2C Hawkeye AWACS (Airborne Warning And Control System) aircraft, and the only country to operate the Boeing E-767, a persistent AWACS platform equivalent to the E-3 Sentry.

The issue, however, is that Japan has limited power-projection capabilities. Of the JSDF’s 247,150 active-duty soldiers, 150,700 serve in the Japan Ground Self-Defense Force (JGSDF). Almost all of Japan’s 55,900 reservists are ground-force reservists. 

Moreover, Japan’s ground forces are not optimized for rapid deployment. Japan is divided into five military districts, with each district fielding a mix of divisions and brigades designed for local deployment. Japan has only two rapidly deployable ground units, the Amphibious Rapid Deployment Brigade – Japan’s naval infantry equivalent – and the 1st Airborne Brigade.

Japan must also consider the possibility of concurrent Sino-Russian action. Depending on the economic effects of the Ukraine war, Russia may be forced to turn to China for explicit economic and political support, raising the prospect of coordinated Sino-Russian military planning. 

Additionally, the PLA’s possible first strikes against Japan – alongside potential Russian naval pressure – would increase the JMSDF’s and JASDF’s home defense requirements. Thus it is the JGSDF that is most free to deploy during a cross-Strait conflict, but also the JSDF component least capable of such a deployment.

The United States should embrace the opportunity that Japan’s shift in defense strategy has provided it. Two steps are crucial. 

First, the US should encourage a joint planning group, composed of Japanese, Taiwanese and American command and staff officers at multiple levels to delineate lines of effort, identify areas of responsibility, and develop joint operational concepts. This formal defense planning would make more robust Japanese and American general pledges to come to Taiwan’s defense.

Second, the US should encourage Japan to forward-deploy several of its infantry brigades to the Ryukyus, rather than concentrating them on Japan’s home islands. Chinese strikes and natural combat attrition would prevent Japan from surging these forces to the Taiwan Strait. By placing them there before a conflict begins and arming them with the weapons needed to counter Chinese naval, air, and amphibious forces, they could disrupt a PLA push around Taiwan and into the Philippine Sea.

After Russia’s 2014 invasion of Ukraine, the US provided limited assistance to Kiev. This was a pittance of what was needed despite the evidence that predatory warfare along traditional lines in Europe remains very much alive.

The satellite images of a military target in Xinjiang province that Nikkei Asia published, together with China’s extraordinary military arms buildup, prove that substantially increased US-Japan defense cooperation is imperative before a crisis in the Taiwan Strait, not when it happens.    

Seth Cropsey is founder and president of Yorktown Institute. He served as a US naval officer and as deputy undersecretary of the navy, and is the author of the books Mayday and Seablindness.