Japan's right-wing politicians have a habit of presenting dangerous deviations from the postwar international order as "modest adjustments" to an "increasingly difficult" security environment. The latest example is the growing campaign to acquire US nuclear-powered submarines.
Ever since Sanae Takaichi became Japan's prime minister, her government's advocacy of nuclear-powered submarines, particularly by Defense Minister Shinjiro Koizumi, has become conspicuous, with the United States portrayed as an eager promoter behind the scenes.
According to reports in the Japanese media, to circumvent Japan's prohibition on possessing nuclear weapons, Washington has even proposed the argument that nuclear propulsion does not mean nuclear armament. This is technically correct: nuclear-powered submarines are not nuclear-armed submarines. But introducing them to Japan would expand the country's strategic and technological options in ways that deserve far more scrutiny than Tokyo's reassuring rhetoric suggests. One must not forget that Japan already possesses substantial nuclear technology and stockpiles of separated plutonium.
The Takaichi government is intent on challenging the Three Non-Nuclear Principles in other ways. The proposed inclusion of research into nuclear-powered submarines thus fits a familiar salami-slicing strategy: replace a clear political decision with seemingly harmless discussions, gradually normalize what was previously taboo, and eventually present the resulting fait accompli as an unavoidable response to circumstances.
But the danger extends beyond submarines. Takaichi's call for removing the "enemy-state clauses" from the United Nations Charter signals impatience with the restraints and historical responsibilities embedded in the postwar international order. A government seeking to loosen nuclear constraints while questioning the institutional legacy of World War II is sending a message that its ambitions extend beyond ordinary "defense" capacity.
Japan's carefully cultivated image as a polite, refined and peace-loving nation makes this transformation particularly difficult for some to notice. Courtesy, punctuality and meticulous attention to social conventions are admirable qualities, but they are no substitute for historical honesty or moral responsibility. The real test of a country's refinement is not how impeccably it observes etiquette, but whether it can distinguish right from wrong, acknowledge the suffering it inflicted, and respect history and the rights of its neighbors.
The portrayal of Japan as an innocent victim of war, while dodging responsibility for aggression, gradually shifts public attention away from historical accountability. Through television dramas, cartoons, entertainment-oriented military publicity and AI-generated content poisoned by neo-militarists, revisionist narratives are packaged as popular culture. Tokyo's objective is to make military expansion appear "unavoidable", "patriotic" and "defensive". A polished public image can conceal a deeply troubling political direction.
Japan's neighbors therefore have particular reason to remain vigilant. The country has yet to reckon with its wartime aggression, and questions of compensation and historical responsibility remain contested. Some of its Cabinet members proudly visit the notorious Yasukuni Shrine, where 14 convicted Japanese Class-A war criminals from WWII are "honored", while its prime minister has come up with an outlandish way of "worshipping from afar".
A nuclear-capable Japan, freed from the political constraints without having completed the corresponding historical reckoning, would fundamentally alter the security calculations of East Asia.
Washington, too, should reconsider the wisdom of indulging these ambitions. Some US strategists appear to regard a more heavily armed Japan as a convenient forward outpost for containing China. But they should remember that strategic subordinates do not necessarily remain subordinate once they acquire sufficient military capabilities. It would be dangerously complacent to assume that a future Japanese nuclear arsenal would remain permanently aligned with US strategic interests.
The lesson of history is that military power without historical responsibility is a recipe for instability.
