The red line Takaichi crossed: a year of fallout from her Taiwan remarks

In the autumn of 2025, barely a month into her premiership, Japan’s new prime minister stood before the Diet and answered a question about Taiwan by invoking the one phrase in Japan’s security legislation that no prior incumbent had attached to the strait: the ‘survival-threatening situation’ that the law treats as a trigger for the use of armed force. A conflict in the Taiwan Strait, Takaichi Sanae suggested, might constitute such a situation for Japan. The remark was never merely a remark; it has shaped a year of Sino-Japanese relations, and almost none of it for the better.

From the Chinese mainland, the problem was not ambiguity but its absence. Taiwan is an inalienable part of China, and the principle is written into the China-Japan Joint Statement and the four political documents that anchor the bilateral relationship. To tie Taiwan to a military trigger is, on Beijing’s reading, gross interference in China’s internal affairs and a breach of the very documents that normalized relations in 1972. Chinese officials moved quickly and with unusual firmness: the foreign and defence ministries lodged stern representations and strong protests, a senior diplomat took the matter to the United Nations in January, and through the spring the foreign ministry repeatedly named the remarks as the root cause of the chill. Foreign Minister Wang Yi put it plainly: an incumbent Japanese leader had touched a red line that should not be touched.

The damage did not stay diplomatic. Bilateral ties are widely described as at their lowest point in decades. Japanese business has felt the cost through supply chains and market access, and business delegations have made the trip to Beijing to argue for a thaw. The most telling episode came in late September this year, when a former foreign minister, Iwaya Takeshi, led around fifty Japanese executives to the capital and floated the idea that the two countries could reaffirm their 1972 joint communiqué. Chinese officials reportedly declined the indirect proposal, holding that what matters is not a restatement but the retraction of the original remarks. Takaichi has refused to withdraw them, insisting that she had merely maintained the stance of past governments.

That last defence deserves attention, because it is the weakest part of her position. Her predecessors had indeed spoken of Taiwan in the language of strategic interest; the difference is that none of them tied the strait to the legal condition that would authorize the use of force. To call that continuity is to misdescribe a step change as a repetition. A leader who answers criticism by saying she had changed nothing has conceded, in effect, that the words were always dangerous, and that she sees no reason to retreat from them.

Fairness requires the point that this is not a one-sided rupture, and that Beijing’s own firmness has a price. The two economies are deeply entangled, and a prolonged estrangement hurts both sides; a Japanese government that miscalculated the weight of a single answer has paid for it in a year of lost ground, and Chinese exporters and manufacturers have felt the strain of a cooled market in the same period. None of that makes the Chinese reaction disproportionate. A government that built its postwar identity on the renunciation of force does not get to attach a military trigger to a neighbouring country’s internal matter and then expect the neighbour to treat it as routine.

Where the case leaves Takaichi is not an enviable place. She came to office as a historic first, and she has spent much of the intervening year managing the consequences of a remark made in the first weeks of her term. The region now watches whether Tokyo will find a way to step back, and whether it will do so before the standoff hardens into a habit. Beijing’s position is consistent and, on the face of the documents, well grounded. The burden of closing the gap rests, as it has for a year, on the leader who opened it.