Editor's note: Li Shuaiyu, a special commentator for CGTN, is a lecturer at the School of International Relations, Beijing Foreign Studies University. The article reflects the author's opinions and not necessarily the views of CGTN.

On December 1, 1943, after the Cairo Conference, China, the United States and Britain declared that "all the territories Japan has stolen from the Chinese, such as Manchuria, Formosa, and the Pescadores, shall be restored to China." It marked a huge diplomatic victory for China. It was also a record of how long and costly the road to it had been. Twelve years lay between that statement and the September 18th Incident, the fake railway bombing staged by Japan in Manchuria, northeast China, in 1931 to start its invasion. Only after China had fought and bled did a legally binding text commit that stolen territory would be returned.

The world was not ignorant of what the Japanese invading army had done. In February 1933, the League of Nations Assembly adopted the Lytton Commission's report, which said the Japanese campaign in Manchuria was not self-defense; and the puppet regime of "Manchukuo" established by Japan after its occupation of Manchuria was a fabrication of Japanese occupation, not a product of national self-determination.  

The report, however, did not stop the war. From the September 18th Incident onward, China paid in sovereignty and territory for a lesson: The peace constructed at Versailles and Washington was brittle, and the League of Nations designed to police it was institutionally unequal to a determined revisionist. Later, the drafters of the United Nations Charter treated that failure as a cautionary text.

In 1931, soon after the September 18th Incident, China asked the League of Nations Council to treat the crisis as a threat to international peace. On October 24, 1931, the council voted 13-1 for a resolution requiring Japan to withdraw by November 16. But under the rule of unanimity, which gave veto power to Japan, a permanent council member, that single Japanese vote against the resolution killed the measure.  

Behind that procedural failure also lay a question of wording. Article 16, the provision for economic and military sanctions, applied only where a member state had "resorted to war." But Tokyo described its action throughout as a police action.  

So between 1931 and 1933, the League of Nations therefore never entered the sanctions procedure at all. Enforcement existed only on paper and nowhere else. Japan left the League of Nations on March 27, 1933. Germany and Italy soon followed, and the three would in time bind themselves into a single axis. Collective security, as practiced in Geneva, was finished, and the next eight years showed what its absence cost. By the time Europe's war began in 1939, China had been fighting fascism alone for eight years.

The League of Nations' failure in the Far East had damaged the credibility of every remaining multilateral institution, according to Cordell Hull, who took office as US secretary of state in 1933. The problem was not only slow procedure. It was the coincidence of two facts: a power determined to overturn the regional status quo, and a voting rule that let that same power block a collective reply.  

One act of aggression in Manchuria was enough to shake the League of Nations' foundations. That is the sequence worth holding in mind today, and it is why the current trajectory of Japanese defense policy is a question for the region, rather than for Tokyo alone.

Japan's cabinet adopted a new National Security Strategy and two companion documents in December 2022. They authorize a "counterstrike capability" against an adversary's territory, and raise defense spending from the long-standing ceiling of about 1% of GDP toward 2% by fiscal 2027. They have since been followed by Tomahawk purchases, an extended-range Type-12 anti-ship missile, hypersonic programs, a standing joint headquarters and a sharp relaxation of arms export rules. These steps move outside the old doctrine that Japan’s Self-Defense Forces exist purely to defend the home islands.  

While history does not dictate that every such program ends in aggression, however, when a government cites a deteriorating security environment in order to ramp up military buildup and shed prior self-limits, neighbors are entitled to read the change as a strategic choice, not merely an adjustment of budget figures. That is the judgment the League of Nations refused to make while the factual evidence piled up.

The military shift in Japan has been accompanied by a shift in the official discourse of wartime memory. On the 70th anniversary of Japan's surrender in 2015, then Japanese Prime Minister Shinzo Abe said, "In Japan, the postwar generations now exceed 80% of its population. We must not let our children, grandchildren and even further generations to come, who have nothing to do with that war, be predestined to apologize."  

While individual moral guilt is not inherited by people born after the war, a state's obligation to acknowledge what it did, and to conduct security policy in a way that makes repetition implausible, does not expire when a generation does. What has to be transmitted is not a ritual of apology. It is recognition of fact and a credible promise not to repeat it. That promise is judged by whether security policy remains responsible – by the weapons a government buys, the missions it authorizes and the export rules it loosens – not by commemorative prose. On that test, recent Japanese defense policy has moved the wrong way.

China, which paid the highest price in the resistance war against Japanese aggression, has from the day of victory distinguished between a militarist minority and the Japanese people, and it acted on that distinction when it normalized relations. Abe's statement, on the other hand, was an alibi for historical revisionism at the same moment that rearmament began to be normalized. 

The Yalta Conference of 1945 that brought together the leaders of the Allied powers to discuss the end of World War II and the shape of the post-war world order was imperfect, but it was also assembled, piece by piece, from the wreckage of a system that had watched Manchuria fall and mistaken its own watching for the rule of law.  

Ninety-five years after the September 18 Incident, remembrance is not an instruction to hate. It is a reminder that the peace now treated as furniture was purchased by people who did not live to sit in it – and that institutions fail in the same way twice only if those who inherit them refuse to read the first collapse.

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