Even with warnings that the West Asia and Ukraine conflicts could escalate into a nuclear weapons exchange, this year’s Hiroshima Peace Declaration did not begin with words of remembrance alone.
They warned of the failure of the Nuclear Non-Proliferation Treaty (NPT). The catastrophes of 5 and 8 August 1945 are not memories sealed off in the past -- they are directly connected to a present in which nuclear weapons are once again invoked as a means of projecting state power and coercing adversaries.
Hiroshima mayor Kazumi Matsui described a world in which distrust breeds retaliation, and retaliation is used to justify further violence. Such cycles, he warned, could ultimately result in “another Hiroshima or Nagasaki”.
UN under-secretary-general and high representative for disarmament affairs Izumi Nakamitsu also delivered a message from Secretary-General António Guterres that distilled the warning into a single question: What has humanity learned from Hiroshima?
This was not a rhetorical flourish. It was an account of a world in which decades of nuclear arms reductions are being reversed, the norm against nuclear testing is under strain, military spending is surging and nuclear threats are increasingly used as instruments of intimidation.
Will the world continue to call an order sustained by ‘fear security’? Or will it restore dialogue, diplomacy, international law and trust.
At the heart of the Peace Declaration was not nuclear strategy, but human experience. It recalled a woman who could never forget her sister, whose skin had peeled away and whose face had been horribly disfigured by the bombing.
It spoke of another woman who was exposed to the bomb at the age of 3, suffered repeated illnesses and lived in fear of what disease might strike next.
And there was a man who survived the bombing at 9. Watching civilians die in Russia’s invasion of Ukraine, he told young people that building a world without conflict must begin with overcoming the impulse toward conflict within themselves and making an effort to understand the perspectives of others.
Such testimonies are reminders that the damage caused by nuclear weapons does not end with the blast. Radiation-related illness, the loss of family, discrimination and anxiety about the future can shape a life for decades.
As the number of hibakusha atomic bomb survivors declines, the importance of their words only grows. Their testimony is more than a record of tragedy. It is evidence that brings the abstract concept of nuclear deterrence back to the reality of human bodies and human lives.
NUCLEAR BARGAIN
To understand the present crisis, it is necessary to examine the bargain on which the NPT rests.
Non-nuclear-weapon states agree not to acquire nuclear arms. Nuclear-weapon states undertake to pursue nuclear disarmament in good faith. And all parties retain the right to the peaceful use of nuclear energy under international safeguards.
The framework was never complete. India, Pakistan and Israel remain outside the treaty, while North Korea has declared its withdrawal. Nor have the nuclear-weapon states recognised by the treaty fully honoured their longstanding commitment to disarm.
At the 2026 Review Conference, that imbalance collided with intensifying geopolitical conflict.
One dispute over the final document concerned language stating that Iran must not seek nuclear weapons. The United States and others pressed for stronger wording on Iran’s uranium enrichment and its cooperation with the International Atomic Energy Agency (IAEA). Iran objected to being singled out and argued that attacks by the United States and Israel on its nuclear facilities had themselves damaged international law and the nonproliferation regime.
But Iran was not the sole cause of the breakdown. It was where a deeper fracture came to the surface.
In the war in Ukraine, the safety of nuclear-related sites, including the Zaporizhzhia Nuclear Power Plant, has repeatedly been placed at risk. A zone free of nuclear weapons and other weapons of mass destruction, first promised in 1995, has still not been established in West Asia.
And under AUKUS, the security partnership among Australia, Britain and the United States, the planned transfer of nuclear-powered submarine technology to a non-nuclear-weapon state has raised questions about safeguards and the precedent it may set.
Meanwhile, China is expanding its nuclear forces, arms control between the United States and Russia is receding, and all nine nuclear-armed states are modernising their arsenals. If nuclear powers and their allies place ever greater importance on deterrence while demanding restraint only from non-nuclear states, suspicion will inevitably grow that the treaty is less a mechanism for preventing proliferation than a system for preserving the privileges of those that already possess the bomb.
But institutions do not always collapse overnight. Each time promises are deferred, criticism of violations is applied selectively and a conference ends without agreement, a little more faith is lost in the NPT.
Nonproliferation and disarmament are two sides of the same coin. Nuclear-weapon states cannot indefinitely demand that others forgo nuclear arms while failing to meet their own obligations. The problem is not the wording of the treaty. It is whether governments still believe in the bargain it represents.
The New Strategic Arms Reduction Treaty, or New START, which imposed verifiable limits on the strategic nuclear forces of the United States and Russia, expired on 6 February 2026. For the first time in more than half a century, the strategic arsenals of the two countries that possess most of the world’s nuclear weapons are no longer subject to legally binding limits.
The norm against nuclear testing is also under pressure. In 2025, the US spoke of resuming ‘testing’ becoming the only country to vote against a draft resolution in the UN General Assembly’s First Committee calling for the entry into force of the Comprehensive Nuclear-Test-Ban Treaty, or CTBT.
Even if no explosive test takes place, ambiguity from a major power about its support for a longstanding norm can give other countries a pretext to weaken it in turn.
According to the Stockholm International Peace Research Institute (SIPRI) global military expenditure reached a record $2.887 trillion in 2025. Spending rose by 14% in Europe and by 8.1% in Asia and Oceania.
Every government has an explanation: Russia’s invasion, China’s rise, uncertainty about alliance commitments, preparations for regional conflict. Considered separately, each can be understood as a response to a security concern. But one country’s defense appears to another as a threat.
Supporters of nuclear deterrence point to the fact that nuclear weapons have not been used in war since Hiroshima and Nagasaki as evidence that deterrence works. Yet there have also been numerous episodes in which false alarms, equipment failures, misread intelligence or errors of judgment brought the world dangerously close to nuclear war.
Luck is not a security strategy. Nuclear deterrence requires every future leader, every intelligence assessment and every communications system to function correctly in every crisis. As artificial intelligence is incorporated into warning and command-and-control systems, faster decision-making could also leave less time to recognise and correct a mistake.
Whether nuclear deterrence played a role in the past and whether it can remain safe indefinitely are not the same question.
Against this backdrop, the first Review Conference of the Treaty on the Prohibition of Nuclear Weapons, or TPNW, will meet at United Nations headquarters in New York in November. The conference will be presided over by South Africa, a country that once dismantled its own nuclear arsenal.
The TPNW comprehensively prohibits the development, testing, production, possession, use and threat of use of nuclear weapons. It also requires states parties to assist people harmed by nuclear weapons use and testing and to remediate contaminated environments.
That is where it differs from the NPT. While the NPT primarily manages the relationship between nuclear-weapon and non-nuclear-weapon states, the TPNW treats nuclear weapons themselves as a humanitarian issue and a matter of international law. It asks not who should be permitted to possess nuclear arms, but whether possessing them can be considered acceptable at all.
The TPNW has an obvious limitation. No nuclear-armed state has joined it, and the treaty alone cannot compel the elimination of nuclear warheads. Ignoring that fact would obscure the distance between establishing a prohibition and achieving actual disarmament.
But three consecutive failures at NPT Review Conferences have also shown that waiting for agreement among the nuclear powers will not produce progress on its own.
The NPT can preserve the legal obligation to disarm, while the TPNW develops the norm of prohibition and practical approaches to victim assistance, environmental remediation and verification. The two treaties can be treated not as rivals, but as complementary frameworks, each addressing gaps left by the other.
A future lived under the shadow of nuclear fear may not be chosen all at once by a single leader. It can also be chosen through an accumulation of small acts of acceptance: tolerating nuclear threats when they come from one’s own side, equating military expansion with security, and confining the testimony of atomic bomb survivors and nuclear test victims to commemorative anniversaries.
What Hiroshima offered the world this year was not an optimistic prediction. It was a choice. A future in which humanity continues to balance one nuclear terror against another — or a future in which nations build a common security that no longer requires nuclear weapons.
No one needs to be an expert to answer that question, and no one needs to wait for a government’s permission. Can security that depends on the threat of incinerating cities truly be called security? Asking ourselves that question is the first political act.
From INPS Japan in collaboration with Soka Gakkai International.