After several weeks marked by suspended flights, bans on Japanese seafood imports, cancelled cultural events performed to empty arenas, stepped-up military activity, and even reported fire-control radar lock-ons by fighter aircraft, relations between Japan and China remain deeply strained. While the immediate trigger for the latest downturn may have been a sharp exchange over Taiwan, the episode has exposed longer-term structural disagreements that suggest tensions between Tokyo and Beijing are unlikely to ease any time soon.
The most recent spat was set off on Nov 7, when Japanese Prime Minister Sanae Takaichi responded to parliamentary questions from opposition lawmaker and former foreign minister Katsuya Okada. Asked about potential crisis scenarios involving a Chinese blockade of Taiwan, Ms Takaichi said that if China launched military action against Taiwan and attacked US military forces, the situation could constitute a “survival-threatening situation” for Japan. She stressed that any response would need to be considered comprehensively.
The phrasing was legally and politically significant. Under Japan’s security legislation, a “survival-threatening situation” denotes an existential threat to the nation, allowing the activation of Japan’s Self-Defence Forces in support of allies. Ms Takaichi became the first sitting Japanese prime minister to publicly describe such a concrete scenario involving Taiwan and US forces.
Beijing reacted angrily, accusing Japan of provocation and of supporting Taiwan independence. It demanded that Tokyo retract the remarks. Adding to the diplomatic storm, China’s consul-general in Osaka posted — and later deleted — a Japanese-language social media comment stating that the “filthy head … must be cut off without hesitation,” language that shocked many in Japan and further inflamed public opinion.
Behind the heated rhetoric, however, lie at least three distinct and enduring issues that explain why Japan–China tensions are unlikely to dissipate even after the current crisis fades.
The first fault line concerns Japan’s political relationship with Taiwan. Like most countries, Japan does not officially recognise Taiwan’s government. In 1972, Tokyo severed diplomatic ties with the Republic of China and established formal relations with the People’s Republic of China. The joint communique stated: “The Government of Japan recognises the Government of the People’s Republic of China as the sole legal Government of China.”
Crucially, the document went on to say: “The Government of the People’s Republic of China reiterates that Taiwan is an inalienable part of the territory of the People’s Republic of China. The Government of Japan fully understands and respects this stand of the Government of the People’s Republic of China.” The wording stopped short of explicit agreement or acceptance. Tokyo has long maintained that it “understood and respected” Beijing’s position without endorsing it.
The reference to Article 8 of the Potsdam Proclamation further underscored Japan’s postwar territorial limits to its main islands. This position aligns with the 1951 San Francisco Peace Treaty, under which Japan renounced claims to territories including Korea, Formosa (Taiwan), and various island groups, without specifying to whom sovereignty was transferred — except in the case of Korea’s independence.
In effect, Japan and China agreed to disagree, or at least to overlook their differences, when normalising diplomatic relations. That deliberate ambiguity remains at the heart of Japan’s “one China” policy today. Tokyo recognises only the PRC as a state but leaves Taiwan’s status unresolved.
This contrasts sharply with Beijing’s “one China principle,” which asserts that Taiwan is an inalienable part of China under the sole legitimate government in Beijing. Chinese officials have long expressed dissatisfaction with the San Francisco Treaty, with a foreign ministry spokesperson recently dismissing it as “illegal” and “invalid.”
In the latest dispute, Ms Takaichi and her government reiterated that Japan has not deviated from its long-standing policy. Yet for Beijing, any discussion of Taiwan in security terms is seen as crossing a red line.
The second issue is Taiwan’s geographic significance, independent of its political status. Publicly available maps show the island sitting astride vital sea lanes, air routes, and submarine cables linking Northeast and Southeast Asia.
For Japan, these routes are existential. Most of its energy imports and a significant portion of its trade, telecommunications traffic, and financial flows pass through Southeast Asia and onward via the Indian Ocean, the Middle East, Africa, and Europe. Any serious disruption caused by a Taiwan crisis would impose devastating costs on the world’s fourth-largest economy — and ripple across East Asia.
Seen in this light, the parliamentary exchange between Mr Okada and Ms Takaichi can be interpreted less as a statement about Japan–Taiwan political relations and more as an acknowledgment of Taiwan’s physical location and its implications for Japan’s national survival. Geography, in this sense, leaves Tokyo with little room for strategic indifference.
The third and perhaps most constraining factor is Japan’s alliance with the United States. US naval and air power underpin freedom of navigation in the Indo-Pacific, enabling Japan’s economic connectivity with distant markets and suppliers. For decades, reliance on the US security umbrella allowed postwar Japan to keep defence spending low and focus on economic growth and regional engagement.
Today, however, questions about the durability of US forward presence in Asia have grown louder. As a result, Japan has begun investing more heavily in its own defence capabilities and has become more explicit in affirming the importance of the alliance. This makes it politically and strategically difficult for Ms Takaichi to walk back her remarks.
Domestic politics further constrain her options. Japanese public opinion has largely backed the prime minister, reflecting deepening public apprehension toward China. With elections looming, retreating under Chinese pressure would carry significant political costs.
Ms Takaichi’s comments thus reflect a broader shift in Japan’s security calculus rather than an isolated rhetorical misstep.
From Beijing’s perspective, even a more assertive yet still defensive Japan is troubling. While China has benefited from Japan’s historically restrained security posture, it views the US–Japan alliance as a mechanism to “encircle, contain, and suppress” China — a formulation Chinese President Xi Jinping has publicly used since at least 2016.
China’s sharp response may be intended to deter Tokyo from further security alignment with Washington and to reinforce pressure on Taiwan by discouraging third-party involvement. It may also aim to put the Takaichi administration on the defensive early, given the prime minister’s roots in the conservative, more hawkish wing of Japanese politics.
Notably, the Trump administration has refrained from vocally backing Japan amid Chinese pressure, even as it has demonstrated alliance strength through military deployments. This relative silence could embolden Beijing to push harder.
For now, Tokyo appears focused on remaining calm and avoiding escalation. Japan has weathered Chinese economic coercion with relative resilience, despite Beijing’s bluster. Yet even if the immediate crisis subsides, Japanese public mistrust of China is likely to deepen, making future disputes more frequent and potentially more severe.
Across Asia, countries maintain their own versions of “one China” policies, shaped by national interests and geography. While these often differ from Beijing’s interpretation — and from each other’s — none can escape the consequences of a major Taiwan crisis.
As major powers increasingly revisit and reinterpret international laws and understandings, smaller states face eroding safeguards that once reduced uncertainty and restrained coercion. How the current Japan–China spat unfolds may therefore shape not only bilateral ties, but also the broader strategic environment confronting third parties in an increasingly contested Indo-Pacific.
