In the sterilised language of diplomacy, nations typically express displeasure with “grave concerns” or “strong condemnation.” But earlier this month, China’s Consul General in Osaka, Xue Jian, took to social media and posted an unusually personal and violent threat directed at Japan’s new Prime Minister, Sanae Takaichi. What spurred his remark? Takaichi’s statement that a Taiwan emergency is a “survival-threatening situation” for Japan.
How did Beijing react? China summoned Japan’s ambassador, demanded a retraction, and issued travel advisories urging Chinese citizens to avoid visiting or studying in Japan. But it did not stop there. China ramped up coastguard and maritime activity near the disputed Senkaku/Diaoyu Islands and announced that its Premier will not meet the Japanese leader at the upcoming G20 summit.
Is this an overreaction? Yes. But is this the first time that Japan has articulated this position? No. In 2021, then-Deputy Prime Minister Taro Aso (who has been instrumental in Takaichi’s rise) made a similar comment at a fundraising event in Tokyo. The same year, PM Shinzo Abe, speaking virtually to a think tank in Taipei, declared that a Taiwan contingency is a Japan contingency. Abe argued that because Japan’s western islands are so close to Taiwan, any war there would inevitably spill over into Japanese territory, forcing Japan to fight.
Given that Takaichi considers Abe her mentor, it is not a surprise that she echoes his opinion. In recent years, since the leadership of Yoshihide Suga, the US and Japan have repeatedly emphasised in their joint communiqués that peace and stability in the Taiwan Strait are indispensable. What has perhaps rattled China this time has been the bluntness, timing, and public context of Takaichi’s remarks.
Under the 2015 security laws, declaring a situation “survival-threatening” legally allows Japan to activate collective self-defence. This means Japan could legally deploy the Self-Defence Forces to fight alongside the US to defend Taiwan. Upon taking office, Takaichi’s cabinet has also accelerated Japan’s long-planned defence expansion, pledging to reach 2 per cent of GDP in defence spending by 2026, a year ahead of schedule.
For decades, Japan’s nuclear identity has been defined by its Three Non-Nuclear Principles: it shall not possess, produce, or permit the introduction of nuclear weapons. Although this remains the official guideline, her administration has now begun a review specifically of the third principle that may allow US nuclear-armed vessels and submarines to dock at Japanese ports during a crisis.
Beijing’s unease has only grown since President Donald Trump and Secretary of War Pete Hegseth’s visit to Japan last month, during which Takaichi proclaimed a new “golden age of the U.S.–Japan alliance”. This entails a deeper integration through the upgradation of a joint command structure. Tokyo’s recent defence documents also signal a determination to develop counter-strike capabilities, invest in next-generation military technologies and expand security partnerships beyond its traditional alliance framework.
At the ASEAN Defence Ministers’ Meeting-Plus last month, Japan’s new Defence Minister, Shinjiro Koizumi, met with his Chinese counterpart andacknowledged that ‘security remains the most difficult aspect of Japan-China relations’, emphasising the need to ‘persistently continue frank discussions and communication.’ It is unfortunate how quickly and suddenly the tides have changed.
Three reasons help explain the ferocity of China’s reaction. First, China wishes to influence the domestic political debate in Japan. With hawkish political figures gaining prominence, China is using this episode to influence the acceptable boundaries of Japan’s Taiwan debate. For instance, commentaries in Chinese media have been arguing that Takaichi’s comments have undermined the “political foundation of Sino-Japanese relations” and urged criticism from “people of insight” in Japan. Meanwhile, economic coercion, seen in the cancellation of half a million Chinese passenger tickets to Japan and a steep drop in tourism shares, sends a message to Japanese voters, businesses, and moderates that confrontation carries real costs. Another example of this is China’s reimposition of the ban on Japanese seafood imports, effectively reversing the progress made over the last year.
Second, the Chinese response is a warning to other nations in the region. This works on two levels. On the one hand, Beijing is arguing that Takaichi’s wish to revive the spirit of Japanese militarism threatens regional countries. On the other hand, by escalating so swiftly and so visibly, China hopes to deter other Indo-Pacific states from taking positions on the Taiwan issue that do not align with Beijing’s agenda. This fits a pattern of Beijing using pretexts to engage in unprecedented escalation to establish new normals.
Third, the reaction plays directly into China’s domestic politics. Given Japan’s historical role in Chinese political memory, anti-Japanese sentiment has always been an easy lightning rod for nationalist mobilisation. In fact, the issue of Japanese militarism has been a significant part of the national discourse throughout the year. The parade to mark the 80th anniversary of the end of World War II in September was, in fact, one of the most significant events in China’s political calendar in 2025. With economic growth slowing at home, such nationalistic showdowns help reinforce the Chinese Communist Party’s image as the guardian of sovereignty and national dignity.
In an attempt to defuse the immediate crisis, Japan dispatched a senior diplomat, Masaaki Kana, to Beijing earlier this week. However, the diplomatic chill continues to take its toll, with events and survey launches postponed. Regardless of whether the current tensions dissipate, the recent furore over Taiwan illuminates the region’s growing volatility and the degree to which Japan is now willing to speak and act like a consequential security actor.