The nuclear debate is the first and inevitable step toward the emergence of a new, technologically advanced nuclear power in Asia, capable of deterring the ambitions of Beijing and Moscow.

Japanese Defense Minister Shinjiro Koizumi’s statement calling for “a discussion without taboos” on nuclear weapons has officially brought the era of Tokyo’s absolute pacifism to an end. A country that for more than half a century was the world’s leading advocate of nuclear disarmament now faces the harsh reality of 2026.

For Japan’s military establishment, Ukraine’s experience has become the main evidence that paper security guarantees and memoranda do not work. The tragedy of the Budapest Memorandum has ultimately convinced Tokyo that voluntarily giving up nuclear capabilities in exchange for promises of protection is a direct path to the loss of sovereignty.

Surrounded by aggressive dictatorships and facing growing doubts about the reliability of the American “deterrence umbrella,” Japan is taking a historic step toward acquiring the status of a nuclear-armed state. For Tokyo, the time of compromises and illusions has irreversibly passed, while the lessons of the Russian-Ukrainian war have clearly demonstrated to the world that international law without real deterrent power cannot stop an aggressor.

Since 1967, Japan’s security policy has been based on the political doctrine of the “Three Non-Nuclear Principles,” which prohibit possessing, producing, and introducing nuclear weapons. These principles were considered sacred. However, today the government of Prime Minister Sanae Takaichi, relying on a two-thirds constitutional majority in parliament, is openly preparing society for a change of course. The main reason is a radical review of three key national-security documents planned for the end of the year.

Defense Minister Koizumi has stated directly that Japan cannot avoid addressing the nuclear issue. Non-nuclear status no longer guarantees survival, while the principles themselves have never been enshrined in law. They are merely a government declaration that the current cabinet can change with a single vote.

The argument that the time has come is driven by the critical deterioration of the geopolitical situation surrounding the Japanese archipelago and three major threat factors.

First, there is the nuclear environment. Japan is surrounded by three unpredictable autocracies: China, which is rapidly expanding its arsenal; russia, which regularly conducts provocations near Japan’s borders; and North Korea, whose ballistic missiles regularly fall within Japan’s exclusive economic zone.

Second, Tokyo has carefully studied the European experience, including Finland’s example of allowing the deployment of nuclear weapons on its territory after joining NATO, as well as France’s mobilization of resources to strengthen its own strategic forces.

Third, the crisis of confidence in the United States and growing isolationist sentiments in Washington are forcing Japan’s military establishment to ask a sober question: would the United States be willing to sacrifice Los Angeles to save Tokyo? Japan is therefore increasingly considering the need to rely on itself.

Japan’s main secret is that it does not need decades to develop nuclear technology from scratch. The country is effectively a “six months from the bomb” state. It possesses enormous reserves of civilian plutonium, estimated at approximately 45–47 tonnes. After enrichment at the Rokkasho facilities, this quantity would technologically be sufficient to produce several thousand warheads. At the same time, the accelerated increase in defense spending to 2% of GDP provides the necessary funding for such a program.

In addition, Japan’s space program, including developments based on the solid-fuel Epsilon rocket series, provides a ready technological foundation for rapidly developing military intercontinental ballistic missiles.

Japan will not secretly assemble a bomb tomorrow, but the roadmap from discussion to implementation is already becoming clear. At the current first stage, the discussion is being legitimized in the media and parliament in order to break the psychological barrier within a society where more than 40% of citizens already support reconsidering the country’s nuclear policy.

At the second stage, planned for the end of the year, the third principle prohibiting the introduction of nuclear weapons is expected to be officially abolished. This would allow the United States to legally deploy its nuclear forces at American bases in Okinawa or Yokosuka during crises. The third stage, in the longer term, could involve the creation of Japan’s own minimal deterrent arsenal in response to further Chinese aggression or a worsening situation in the Taiwan Strait.

For Japan, nuclear weapons are not an instrument of expansion but an ultimate means of preserving sovereignty. The long era of pacifism effectively ended in 2022 with russia’s invasion of Ukraine.

The civilized world has seen that pacifism without strength merely encourages an aggressor. Tokyo is beginning to act, and the nuclear debate is the first and inevitable step toward the emergence of a new, technologically advanced nuclear power in Asia capable of deterring the ambitions of Beijing and Moscow.

Unlike Japan, Kyiv is forced to raise similar questions about nuclear deterrence not preemptively, but in response to the destruction of international law and aggression.

The prospect of Ukraine restoring its own nuclear status has now entered the sphere of pragmatic military planning. Unlike Japan, Ukraine would have to create production lines for weapons-grade material from scratch under wartime conditions. This would require considerable time and provoke strong opposition not only from the russian federation but also from Western allies.

For this reason, a much more realistic scenario for Kyiv would be integration into a nuclear-sharing system modeled on NATO. The deployment of allied tactical nuclear components on Ukrainian territory is, in the expert view, considered the only reliable safeguard against renewed Russian aggression. Under such a scenario, Ukraine in Eastern Europe and Japan in the Far East would become two major outposts of a new global system for deterring autocracies.

Mykola Zentsev, international security expert, retired Major General

Source: Ukrinform