The mayor of Hiroshima on Sunday called on world leaders to accept that rising international instability has proven nuclear deterrence to be a "folly" as it marked the 78th anniversary of its atomic bombing by the United States.

Hiroshima Mayor Kazumi Matsui reads out the Peace Declaration during a ceremony marking the 78th anniversary of the U.S. atomic bombing of Hiroshima on Aug. 6, 2023, at the Peace Memorial Park in the Japanese city. (Kyodo)

Hiroshima Mayor Kazumi Matsui's message at a ceremony came as the western Japan city reflects on hosting the Group of Seven major economies' summit in May, during which the leaders, including some from nuclear-armed countries, visited the peace park and its museum on the bombing's effects before releasing a statement backing deterrence principles.

But while he welcomed their engagement with the city in this year's Peace Declaration, Matsui said, "Leaders around the world must confront the reality that nuclear threats now being voiced by certain policymakers reveal the folly of the theory of nuclear deterrence."

"They must immediately take concrete steps to lead us from the dangerous present toward our ideal world," he added. He also urged Japan to join the Treaty on the Prohibition of Nuclear Weapons and participate at least as an observer at the second meeting of the parties to the treaty, set for November.

People pray in front of the cenotaph at the Peace Memorial Park in Hiroshima, western Japan, on Aug. 6, 2023, the 78th anniversary of the U.S. atomic bombing of the city. (Kyodo) 

At the ceremony, a moment of silence was observed at 8:15 a.m., the exact time when the uranium bomb was dropped by the U.S. bomber Enola Gay and detonated over the city on Aug. 6, 1945, killing an estimated 140,000 people by the end of that year.

Prime Minister Fumio Kishida also spoke at the event, where he said "the widening division within the international community over approaches to nuclear disarmament, the nuclear threat made by Russia and other concerns now make that road all the more difficult."

"But it is precisely because of these circumstances that it is imperative for us to reinvigorate international momentum once more towards the realization of a world without nuclear weapons," he added.

A lawmaker whose constituency is in the city, Kishida was instrumental in bringing the G-7 leaders to Hiroshima as part of his aim to promote efforts toward disarmament amid growing fears of nuclear war following Russia's invasion of Ukraine.

Japanese Prime Minister Fumio Kishida delivers a speech at a ceremony to mark the 78th anniversary of the U.S. atomic bombing of Hiroshima on Aug. 6, 2023, at the Peace Memorial Park in the city. (Kyodo)

On the first day of the summit, the leaders of the G-7, including nuclear powers Britain, France and the United States, made an unprecedented joint visit to the Hiroshima Peace Memorial Museum and met 86-year-old atomic bomb survivor Keiko Ogura.

In a statement read by Izumi Nakamitsu, U.N. undersecretary general and high representative for disarmament affairs, U.N. Secretary General Antonio Guterres said that more should follow the leaders' example in visiting the city "because the drums of nuclear war are beating once again."

Matsui, too, welcomed the G-7 leaders' historic visit to the park and its atomic bomb museum, saying it proved the city's hope for peace had reached them. "I believe our spirit is now engraved in their hearts," he said.

But the G-7's first-ever joint document on nuclear disarmament, titled the Hiroshima Vision, has proved more controversial. It calls the Nuclear Non-Proliferation Treaty the "cornerstone" of nonproliferation and the "foundation" for disarmament.

Kishida emphasized the contribution of the vision document, saying, "We succeeded in building momentum once more within the international community for progress in nuclear disarmament" through it and open discussions held at the summit.

The document's reception by atomic bomb survivors, known as hibakusha, has been mixed. A Kyodo News survey conducted after the summit showed the statement was viewed negatively by 51.7 percent of those polled, of which 59 percent cited the lack of any mention of the nuclear ban treaty.

Japan has not participated in the treaty, which went into effect in January 2021 and bans the use of nuclear arms. Instead, it continues to back the nonproliferation treaty.

A ceremony is held at the Peace Memorial Park in Hiroshima, western Japan, on Aug. 6, 2023, the 78th anniversary of the U.S. atomic bombing of the city. (Kyodo)

In a meeting with representatives of atomic bomb survivors' groups after the ceremony, Kishida responded to their calls for Japan to join the ban treaty by saying only that he would work toward getting nuclear-armed nations involved.

The divergence of views on the path to disarmament was apparent among those paying respects at the park.

Kunio Otani, a 77-year-old in-utero survivor who was in his mother's womb when she entered the city in the days after the attack, said the summit had been "one step forward and one back" on disarmament. "It's no good for a prime minister from Hiroshima," he said.

Conversely, Keiko Kubota, a second-generation hibakusha, said the summit and its outcomes were a "big first step."

"I know survivors' groups say it hasn't been effective for disarmament, but I don't agree. It will show its effect from now on," said the 61-year-old, who lost eight family members to the bomb and its subsequent effects.

Among the 50,000 people in attendance at the Hiroshima commemoration were representatives from 111 countries and the European Union, the highest number on record. Like last year, Russia and Belarus were not invited due to the invasion of Ukraine.

People observe a moment of silence at the Peace Memorial Park in Hiroshima at 8:15 a.m. on Aug. 6, 2023, the exact time of the U.S. atomic bombing of the Japanese city 78 years ago. (Kyodo)

One of the attendees reflecting on the attack was Takumi Matsumae, 79, who was a baby when the atomic bomb struck about 1.3 kilometers from the home where he lived with his mother. He was crushed under the fallen building until a passerby heard his cries and lifted him from the rubble to save his life.

"From my youth, I heard about this man I owed my life to. I even tried to go to his home and speak with him many times, but in the end, we never met. Every year, when I come to the ceremony, I think about my gratitude to him, this man I don't know," Matsumae said.

Three days after Hiroshima was leveled by the atomic bomb known as "Little Boy," the United States dropped a second device on the southwestern city of Nagasaki. World War II ended six days later, when Japan surrendered to the Allied forces.

Government figures, as of the end of March, showed there were 113,649 officially recognized survivors of both attacks, down 5,346 from the previous year, with their average age standing at over 85.

While 9,350 hibakusha died in fiscal 2022, the decline in the total figure was partially offset by an expansion in recognitions from April 2022 of some individuals exposed to radioactive "black rain" that followed the bombings.

Gist of Hiroshima Peace Declaration on 78th A-bomb anniversary

The following is the gist of the Peace Declaration read Sunday by Hiroshima Mayor Kazumi Matsui at a ceremony marking the 78th anniversary of an atomic bomb being dropped on the city.

-- Messages left at the Hiroshima Peace Memorial Museum by the leaders who attended the Group of Seven summit indicate that the pleas of atomic bomb survivors had reached them.

-- The G-7 Leaders' Hiroshima Vision on Nuclear Disarmament reaffirms their commitment to a world without nuclear weapons.

-- World leaders must face the reality that nuclear threats today show the folly of nuclear deterrence theory and take steps toward an ideal world.

-- Civil society increasingly needs to urge policymakers to abandon nuclear deterrence in favor of a peaceful world.

-- Policymakers worldwide should follow the footsteps of the G-7 leaders in visiting Hiroshima and sharing the desire for peace.

-- The Japanese government should heed the wishes of hibakusha, or atomic bomb survivors, by reconciling the difference between nuclear and non-nuclear states.

-- Japan must immediately join the Treaty on the Prohibition of Nuclear Weapons and at least observe the meeting of signatories to the treaty in November.

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