With Beijing’s hostile rhetoric trumpeted and its saber increasingly rattled, Taiwanese are naturally looking to Japan to supplement and complement US military power. The sense of necessity is considerable since the US has experienced serious relative decline vis-a-vis China, now compounded severely by the protracted war in Ukraine and the Gaza conflict.
The US might not be able to cope with three concurrent major regional conflicts in Europe, the Middle East and Northeast Asia, and thus is an increasingly less reliable sole security guarantor for Taiwan.
No wonder Taiwanese felt relieved to learn of former Japanese prime minister Shinzo Abe’s statement in December 2021 at an online forum of the Institute for National Policy Research in Taipei: “A Taiwan contingency is a Japan contingency.” This sounds as if the Japan Self-Defense Forces would intervene in the event of a Chinese invasion of the main island of Taiwan.
Abe’s remark seemed a natural progression from the joint statement that came out of the Japan-US joint summit the preceding April between then-Japanese prime minister Yoshihide Suga, who was Japanese chief cabinet secretary under Abe’s premiership, and US President Joe Biden, saying they “underscore the importance of peace and stability across the Taiwan Strait and encourage the peaceful resolution of cross-Strait issues.”
In August, Liberal Democratic Party (LDP) Vice President Taro Aso, a former Japanese prime minister, delivered a speech at the Ketagalan Forum in Taipei emphasizing the importance of “Japan’s will to fight” alongside the US and Taiwan to deter China from waging a regional war centered on Taiwan.
This reinforces the impression that the LDP government is committed to armed intervention in a possible Taiwan contingency.
In polls by the Taiwan Public Opinion Foundation, Taiwanese have consistently said they expect the Japanese “military” to intervene in the event of a Taiwan contingency and see it only slightly less plausible than US military intervention. Immediately after the outbreak of Russian aggression against Ukraine, their expectations regarding Japanese and US intervention reversed.
However, given Japan’s constitutional and other legal constraints, and its established policy of “exclusively defensive defense,” Taiwanese’s expectation is totally unwarranted.
Under its postwar constitution, Japan “renounce[s] war as a sovereign right of the nation and the threat or use of force as means of settling international disputes,” and does not recognize the “right of belligerency of the state.”
China’s aggression against Taiwan would never constitute an armed attack on Japan and thus would never justify Japan’s “military” fighting against Chinese forces. Japan also lacks any international legal grounds for such military action, because Tokyo abandoned the title of Taiwan’s suzerain by concluding the San Francisco Peace Treaty of 1952 without reassigning it to any party. This means that Japan’s armed forces could never openly fight for Taiwan.
Certainly, the Abe administration in 2015 reinterpreted the constitution in a way that enabled limited exercise of the right of collective self-defense. This is deeply entrenched in the Three Strategy Documents from December last year that are seen as highly active and unambiguous in exerting deterrence against China.
The following three conditions for use of force were set: when an armed attack against Japan has occurred, or when an armed attack against a foreign country that is in a close relationship with Japan occurs and as a result threatens Japan’s survival and poses a clear danger to fundamentally overturn people’s right to life, liberty and pursuit of happiness; when there is no appropriate means available to repel the attack and ensure Japan’s survival and protect its people; and use of force is limited to the minimum extent necessary.
This applies to the defense of US bases, facilities and forces in Japan and US forces on combat missions in the operational theater of the Far East, including Taiwan, given the US is its sole treaty-based ally.
A full-scale Taiwan contingency would most likely involve China attacking the US air base in Kadena on the main island of Okinawa and the Senkaku Islands, known as the Diaoyutai Islands (釣魚台群島) in Taiwan. The Self-Defense Forces would take maximum defensive action against such attacks, which would indirectly, but significantly contribute to the defense of Taiwan. This excludes the possibility that the Self-Defense Forces become involved in a limited Taiwan contingency that occurs primarily over the Taiwan Strait and the main island of Taiwan.
Conversely, Japan’s unilateral intervention basically cannot be authorized and is operationally infeasible due to the dearth of Japan’s power projection capabilities, which would only be available after the completion of a 10-year arms buildup plan that has been agreed to, but essentially still exists only on paper.
Hence, Japan’s armed intervention is plausible in a full Taiwan contingency only through the Japan-US alliance. There would be no unilateral intervention at all.
The political rhetoric of major Japanese political leaders, especially Abe’s, has been heavily constrained by the prevailing domestic policy discourse, which has misled the Taiwanese public and authorities.
It is necessary for Taiwan to recalibrate its expectations of Japan’s intervention and concentrate on reinforcing its own defense capabilities, while enhancing informal defense policy coordination between Taipei and Tokyo.
Masahiro Matsumura is a professor of international politics and national security at Momoyama Gakuin Daigaku, also known as Saint Andrew’s University, in Osaka, Japan.
Taiwan stands at the epicenter of a seismic shift that will determine the Indo-Pacific’s future security architecture. Whether deterrence prevails or collapses will reverberate far beyond the Taiwan Strait, fundamentally reshaping global power dynamics. The stakes could not be higher. Today, Taipei confronts an unprecedented convergence of threats from an increasingly muscular China that has intensified its multidimensional pressure campaign. Beijing’s strategy is comprehensive: military intimidation, diplomatic isolation, economic coercion, and sophisticated influence operations designed to fracture Taiwan’s democratic society from within. This challenge is magnified by Taiwan’s internal political divisions, which extend to fundamental questions about the island’s identity and future
The narrative surrounding Indian Prime Minister Narendra Modi’s attendance at last week’s Shanghai Cooperation Organization (SCO) summit — where he held hands with Russian President Vladimir Putin and chatted amiably with Chinese President Xi Jinping (習近平) — was widely framed as a signal of Modi distancing himself from the US and edging closer to regional autocrats. It was depicted as Modi reacting to the levying of high US tariffs, burying the hatchet over border disputes with China, and heralding less engagement with the Quadrilateral Security dialogue (Quad) composed of the US, India, Japan and Australia. With Modi in China for the
The Jamestown Foundation last week published an article exposing Beijing’s oil rigs and other potential dual-use platforms in waters near Pratas Island (Dongsha Island, 東沙島). China’s activities there resembled what they did in the East China Sea, inside the exclusive economic zones of Japan and South Korea, as well as with other South China Sea claimants. However, the most surprising element of the report was that the authors’ government contacts and Jamestown’s own evinced little awareness of China’s activities. That Beijing’s testing of Taiwanese (and its allies) situational awareness seemingly went unnoticed strongly suggests the need for more intelligence. Taiwan’s naval
The Chinese Nationalist Party (KMT) has postponed its chairperson candidate registration for two weeks, and so far, nine people have announced their intention to run for chairperson, the most on record, with more expected to announce their campaign in the final days. On the evening of Aug. 23, shortly after seven KMT lawmakers survived recall votes, KMT Chairman Eric Chu (朱立倫) announced he would step down and urged Taichung Mayor Lu Shiow-yen (盧秀燕) to step in and lead the party back to power. Lu immediately ruled herself out the following day, leaving the subject in question. In the days that followed, several
RSS