The so-called nuclear taboo that says nuclear weapons should never be used is wavering like never before.

At her July 28 news conference, Hiroshima Governor Mika Yokota said, “The international circumstances surrounding nuclear weapons are very severe and we are amid a crisis in which the taboo might be broken.”

We face a reality that is by no means exaggerated.

Nations that possess nuclear weapons with unfathomable destructive power are ignoring the rules that international society has written and have become directly involved in wars and military conflicts.

International brakes on nuclear weapons have gradually been lost. They have become dysfunctional.

Besides changes in the international situation, nuclear weapons themselves have undergone change. A new threat is spreading in the form of the use of artificial intelligence in military affairs.

If AI should become deeply intertwined with nuclear weapons, it could become the trigger for destruction that is beyond the control of humans.

NUCLEAR POWERS AT WAR

Nine nations are believed to possess nuclear weapons.

The Nuclear Nonproliferation Treaty allows the United States, Russia, Britain, France and China to possess them.

India, Pakistan and Israel also have such weapons although they are not party to the NPT. North Korea is the final power, but it has bolted from the treaty.

Russia invaded Ukraine in 2022, and fighting continues.

This year, the United States and Israel attacked Iran, ostensibly to prevent it from possessing nuclear weapons.

At the same time, the United States has no problem with Israel possessing nuclear weapons.

North Korea has provided Russia with ammunition and troops, while last year Pakistan and India were involved in a military dust-up.

This is a serious situation in which many nuclear powers are involved in war or military conflict.

There are more than 12,000 nuclear warheads worldwide, about 80 percent of them in the hands of the United States and Russia.

The New Strategic Arms Reduction Treaty (New START) between Russia and the United States expired in February, ending a nuclear arms reduction framework.

Those two nations, along with Britain, France and China, have not fulfilled their NPT obligation regarding arms reduction.

In March, France said it would increase its number of nuclear warheads to provide Europe with a nuclear umbrella.

Such moves have stoked concerns among non-nuclear nations. It has led to a negative spiral of wanting to depend on the weapons.

After joining NATO in 2023, Finland this year said it would allow nuclear weapons on its territory.

THREATS FROM AI

AI is evolving at incredible speed. If it is installed in the command and control structure for nuclear weapons, it could lead to the accidental use of such weapons.

It has also become more likely that humans tasked with making an instantaneous decision will simply go along with the analysis and direction provided by AI.

A sense of crisis has heightened among experts.

An international conference was held in Italy in July on the issue of AI and nuclear weapons.

Experts and scientists including Nobel laureates came together to discuss the problem. They released a statement calling for the responsible use of AI and nuclear arms reduction.

There was also a call for an international treaty against adding AI to nuclear systems.

Nuclear powers must share a recognition of the risks and promote dialogue.

They, and nations protected by a nuclear umbrella, have relied on nuclear deterrence based on a balance of fear. This is the belief that no enemy will attack a country with nuclear weapons for fear of retaliation.

But the vast nuclear weapons machine has a persistent risk of glitches as well as misunderstandings and suspicion among the humans operating it.

While nuclear nations are expected to act rationally and make decisions based on accurate information, recent actions by Russia and the United States have led to doubts about that.

Development is also progressing on low-yield nuclear weapons.

There are increasing concerns among experts that such moves could lower the hurdle for using nuclear weapons. Until now those same experts have supported deterrence.

JAPAN’S ROLE

An exhibition room in the Nagasaki Atomic Bomb Museum has a sign that reads: “Make Nagasaki the final place hit by atomic bombs.”

It is a poignant hope.

The atomic bombs dropped by the U.S. military on Hiroshima and Nagasaki in August 1945 took about 210,000 lives in that year alone.

Those who escaped death suffered for many years from the effects of radiation.

Survivors would talk about the inhumanity of nuclear weapons, and they continue to pass on their experiences today.

Those voices became the foundation of the nuclear taboo.

In 2024, the Nobel Peace Prize was awarded to Nihon Hidankyo (Japan Confederation of A- and H-Bomb Sufferers Organizations).

Terumi Tanaka, a representative director of Nihon Hidankyo, said at a July symposium in Nagasaki, “The same suffering should never again be made.”

Despite the critical situation around nuclear weapons, no agreement on arms reduction was reached at the NPT review conference held in April and May.

A review conference is scheduled in November for the Treaty on the Prohibition of Nuclear Weapons (TPNW).

The government must use international conferences and all other opportunities to underscore the horrors caused by nuclear weapons. It must call on nuclear powers to take steps toward reducing and eliminating such weapons

If we continue to stand idly by, the nuclear taboo could be broken.

It is the role of Japan as the only nation to have suffered an atomic attack in war to prevent that from happening.

--The Asahi Shimbun, Aug. 6