Amid increasing global nuclear dangers, it is more important than ever that world leaders hear - and heed - the warnings of the hibakusha.
Thus, the decision to award last year's Nobel Peace Prize to Nihon Hidankyo was not only well-deserved recognition of their decades of tireless and courageous work; it was also an urgent wake-up call.
Unless we change course now, the kind of devastation that was inflicted upon the people of Hiroshima and Nagasaki eight decades ago will almost certainly be repeated.
As the Norwegian Nobel Committee observed last October, the "taboo" against the use of nuclear weapons "is under pressure"1 Furthermore, proliferation risks abound, the nuclear arms race continues apace, and not a single nuclear-armed state has shown genuine commitment in recent years to the goal of nuclear disarmament.
Indeed, we appear to be sleepwalking towards catastrophe.
As the hibakusha have warned time and again, in the starkest terms: "Nuclear weapons and humanity cannot co-exist."
But there is a glimmer of hope that an alternative path will be taken.
Half of the world's countries have now accepted binding obligations under international law never to support nuclear weapons in any way.
They have banded together to lay the legal and normative foundations for a nuclear-weapon-free world.
I am referring, of course, to the states parties and signatories to the landmark Treaty on the Prohibition of Nuclear Weapons, or TPNW.
The UN secretary-general, António Guterres, hailed this treaty's entry into force in 2021 as "an extraordinary achievement and a step towards the eventual elimination of nuclear weapons"2
Not only does it impose a blanket ban on nuclear weapons; it also establishes, for the first time, a legal framework for verifiably eliminating nuclear-weapon programmes in a time-bound matter, and includes novel provisions to assist victims of nuclear use and testing.
The preamble acknowledges "the unacceptable suffering of and harm caused to" the hibakusha, as well as their role - alongside civil society groups, the Red Cross, religious leaders and others - "in the furthering of the principles of humanity" by pursuing disarmament.
In fact, many hibakusha were instrumental in making the TPNW a reality.
They addressed the negotiating conference in 2017 and the preceding conferences on the humanitarian impact of nuclear weapons in Norway, Mexico and Austria.
They collected signatures in the streets and raised public awareness about the urgent need for a ban.
When the final text of the treaty was adopted at the United Nations headquarters in New York, Setsuko Thurlow, a hibakusha from Hiroshima who has been a leading voice in our campaign since its inception, described that moment as "the beginning of the end of nuclear weapons".3
She asked the assembled diplomats and campaigners to "pause for a moment to feel the witness of those who perished in Hiroshima and Nagasaki … hundreds of thousands of people.
Each person who died had a name.
Each person was loved by someone."
For most of the world's governments, the need for a comprehensive prohibition on nuclear weapons was clear given the catastrophic humanitarian consequences of their use.
Anything less than an outright ban would have been inadequate.
The negotiations for the TPNW came about as a result of the deepening global awareness of these consequences.
They followed the same approach as had been adopted for ot her inhumane weapons, such as chemical and biological weapons, anti-personnel landmines and cluster munitions.
Thus, the discourse on humanitarian consequences served as an essential foundation for the prohibition of nuclear weapons.
Our challenge now is to ensure that the TPNW achieves its high aims.
We must work relentlessly to bring more countries on board.
That includes, of course, Japan - and ultimately all nine of the countries currently armed with nuclear weapons.
Those that are not yet willing to accept the treaty's binding obligations should, at the very least, observe TPNW meetings to enhance their understanding of efforts to implement the treaty.
They will also have the chance to share their views and expertise on important topics such as disarmament verification, safeguards and victim assistance.
Japan's voice in these diplomatic discussions would be especially meaningful as the only country to have suffered nuclear attacks in war.
But the ultimate goal must be for Japan and all other countries to join the treaty, not simply observe its meetings.
As the TPNW states parties declared in 2022: "We will not rest until the last state has joined the treaty, the last warhead has been dismantled and destroyed, and nuclear weapons have been totally eliminated from the Earth."4
The states parties have also been unequivocal in their rejection of "nuclear deterrence" theory.
In 2023, they stated: "The perpetuation and implementation of nuclear deterrence in military and security concepts, doctrines and policies not only erodes and contradicts non-proliferation, but also obstructs progress towards nuclear disarmament."5
They pledged not to "stand by as spectators to increasing nuclear risks and the dangerous perpetuation of nuclear deterrence."
No one is safer as a result of the existence of nuclear weapons.
We are all infinitely less safe.
These instruments of terror and mass destruction only contribute to enmity, fear, instability and unparalleled risk.
They serve no useful or legitimate purpose and must be abolished for everyone's sake, as a matter of urgency.
As Guterres said in 2022, "They offer no security - just carnage and chaos.
Their elimination would be the greatest gift we could bestow on future generations."6
We have a duty to the world's children to do everything in our power to advance disarmament, including vehemently resisting all national policies and programmes that perpetuate nuclear dangers and burden future generations with this ultimate menace.
In the event of a nuclear attack against a city today, it is children who would suffer the greatest harm, as they are more vulnerable than adults to the effects of ionising radiation and more likely to sustain life-threatening burn and blast injuries.
This fact alone should spur urgent action by all of the world's governments.
As we approach the 80th anniversaries of the US atomic bombings of Hiroshima and Nagasaki, we must reflect on their enormous human toll, including the death and suffering of tens of thousands of children.
And we must rededicate ourselves to the cause of disarmament.
Weapons that are designed to kill and maim human beings on a massive scale, indiscriminately and across generations, have no place in our world.
(November 2024)
[Melissa Parke]
Melissa Parke is the Executive Director of the International Campaign to Abolish Nuclear Weapons (ICAN), which won the Nobel Peace Prize in 2017 "for its work to draw attention to the catastrophic humanitarian consequences of any use of nuclear weapons and for its groundbreaking efforts to achieve a treatybased prohibition of such weapons."