Eighty years after Hiroshima, Japan debates military expansion and pacifism

A visual simulation of the dropping of the atomic bomb, displayed at Hiroshima’s peace museum. Photo / Chang W. Lee, The New York Times

Nine nations now possess nuclear weapons, which can obliterate and irradiate human settlements in an instant.

Only twice have they been used: 80 years ago when the destructive technology was in its infancy and in the hands of a single country.

On August 6, 1945, in a drastic move thought to have hastened Japan’s surrender in World War II, the United States dropped an atomic bomb on the western Japanese city of Hiroshima.

A US bomber called the Enola Gay released the 4400kg weapon that detonated nearly 600m in the air, creating a massive mushroom cloud and searing the city with temperatures of up to 4000C. The blast and its fallout extinguished about 140,000 lives by the end of the year.

Three days later, another American bomber dropped a second atomic bomb on Nagasaki, to the southwest, killing another 70,000 people.

The destruction of the two cities was followed by Japan’s submission days later, ending its decades of brutal conquest.

However, the bombings also announced a more terrifying age in which human innovation could spark death and destruction on a previously unimaginable scale.

As the flattened city of Hiroshima was rebuilt, it dedicated itself to promoting peace.

Survivors of the atomic bombing have campaigned for a world free of nuclear weapons.

But 80 years on, that dream is fading. Three of Japan’s neighbours – Russia, China and North Korea – are nuclear powers, and Tokyo depends on the American nuclear umbrella to protect it.

With tensions in the Pacific heightening and firsthand memories of nuclear devastation waning, more Japanese are questioning the national commitment to peace at all costs.

Why did Japan go all-in on pacifism after World War II?

The Americans forced it to.

The Imperial Japanese Armed Forces’ harsh invasion of much of Asia, its shock attack on Pearl Harbour and its willingness to sacrifice a generation of young soldiers for the empire, made the victorious Americans adamant that the country should never again wage war.

Japan’s so-called “peace constitution”, drafted by the Americans who occupied the country for nearly seven years, forever renounced war.

Its Article 9 has been interpreted to mean that Japan should never possess a military with offensive capabilities.

In return, the US promised to defend Japan should it come under attack. The security treaty made Japan a beneficiary of the theory of nuclear deterrence, in which the fear of nuclear retaliation is thought to deter a first-strike attack.

So why does Japan have a military?

To take into account these constitutional limitations, Japan’s military is called the Self-Defence Forces.

It cannot take on combat roles in international conflicts.

That hasn’t stopped Japan from expanding its arsenal to counter potential threats from Asian neighbours such as China that, in turn, worry about Japan’s rearmament, given its wartime record.

If budget hikes continue, Japan will soon be among the world’s top military spenders. All of this modern hardware is supposed to be only for defensive purposes, although a debate in Japan about its global military profile has been getting louder.

What do Japanese think of their country’s rearming?

While many in the older generations worry about Japan’s waning commitment to pacifism, younger Japanese tend to be more sanguine.

Supporters of a military expansion say Japan shouldn’t be forced into a defensive crouch forever, especially with security threats ratcheting up in the Pacific. In addition to superpower jousting, Japan has territorial disputes with China, Russia and the two Koreas.

They worry that the US may not always be a constant security guarantor for Japan, especially under President Donald Trump, who has criticised Japan for relying too heavily on the presence of US military bases.

And with first-hand memories of the bombings of Hiroshima and Nagasaki disappearing, most Japanese are now removed from the kind of searing testimony that underwrote the country’s pacifist, non-nuclear stance.

Nippon Kaigi, an ultra-nationalist political bloc that aims to revise Article 9 of the constitution, has significant support among lawmakers from the governing Liberal Democratic Party.

Amending the constitution was once unthinkable; it’s now a political talking point.

What about nukes?

Nihon Hidankyo, a group representing atomic bomb survivors, was awarded the Nobel Peace Prize last year for its campaign to rid the world of nuclear weapons.

However, Japan has never signed the Treaty on the Prohibition of Nuclear Weapons.

In 2023, Fumio Kishida, then the Prime Minister of Japan, whose family is from Hiroshima, supported a statement at a Group of Seven summit he hosted in the city that implied nuclear deterrence might bring its own kind of peace.

Kishida’s stance reflects a growing feeling in Japan that while nuclear weapons are dangerous and their eradication is a noble ideal, the real world also requires deterrence and robust defence.

This article originally appeared in The New York Times.

Written by: Hannah Beech

Photograph by: Chang W. Lee

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