The Group of Seven leaders' statement on a world without nuclear weapons restating their commitment to non-proliferation principles split experts by offering few surprises, but the Hiroshima summit found them nevertheless agreeing on the value of its symbolism.

The outcome document, the Hiroshima Vision on Nuclear Disarmament released at the end of the first day of the summit, was in line with the existing deterrence policy backed by nuclear states.

It affirmed the Treaty on the Non-Proliferation of Nuclear Weapons as the "cornerstone" for disarmament, disappointing atomic bomb survivors calling for nuclear abolition instead, and leaving experts divided over its implications.

It came just hours after the world saw the leaders of three nuclear-possessing nations -- the United States, Britain and France -- and the other G-7 members make history by jointly visiting the Hiroshima Peace Memorial Park and the museum dedicated to passing on the story of the U.S. atomic bomb attack on Aug. 6, 1945, that levelled the city.

Japanese Prime Minister Fumio Kishida holds a press conference following the conclusion of the three-day Group of Seven summit in Hiroshima on May 21, 2023. (Kyodo)

And while what the leaders saw and discussed inside remains largely unrevealed, the visit was a key moment in the summit hosted by Prime Minister Fumio Kishida, who seized on anxieties over rising nuclear tensions following Russia's aggression in Ukraine to remind the world of the dangers of the bomb.

His initiative delivered many firsts and key moments, with the series of museum visits by not just the G-7 leaders but also major "Global South" players including the leaders of Brazil and nuclear India, as well as Ukrainian President Volodymyr Zelenskyy and South Korean President Yoon Suk Yeol.

Hirofumi Tosaki, the director of the Center for Disarmament, Science and Technology at the Japan Institute of International Affairs, praised the summit for achieving a "brilliant result."

He said that it was because "the G-7 leaders, including those of three nuclear states and four of their allies, discussed past and present nuclear issues while engaging with the reality of the inhumane suffering and damage caused by the bomb, and were united in reaffirming their commitment to disarmament and non-proliferation."

Referring to the crowd of pressing issues facing the world, and the surprise appearance of Zelenskyy, Tosaki said it was significant that a standalone statement on disarmament was released during "one of the most important summits in history."

Despite the praise, however, he said that expecting change from the G-7 was "a little too optimistic."

"Even if we want to disarm, we have to move ahead with Russia, with China. And they're not doing that right now, so I think it's difficult to say what will change," he said.

"But with threats rising, I think we have to think seriously about not using them. If not using them was in some way of benefit to Russia and China, then I'd like to see actions for that purpose taken," he said.

In the lead-up to the summit, anti-nuclear groups, atomic bomb survivors and major figures including U.N. Secretary General Antonio Guterres had called for a plethora of commitments including pledging "no first use" of nuclear arms and to provide a plan for joining the 2017 Treaty on the Prohibition of Nuclear Weapons.

The nuclear states and those protected under the U.S. nuclear umbrella, including host nation Japan, have not participated in the treaty, and no mention of it was made in the latest declarations on disarmament from the leaders.

Among survivors who rejected adherence to non-proliferation principles was atomic bomb survivor Setsuko Thurlow, a prominent anti-nuclear campaigner who backs abolition of the weapons.

In a press conference after the leaders wrapped up the summit, she said the document's total lack of reference to the nuclear ban treaty had been "one-sided" and dubbed the summit a "huge failure."

"I think it was very one sided, they pointed fingers at Russia, North Korea, Iran, China, asking for transparency...But what about them? These are the first countries to develop nuclear weapons, other countries here with nuclear weapons like India are here for the summit, and they didn't reflect at all on what they are doing."

Daniel Hogsta, interim executive director of the International Campaign to Abolish Nuclear Weapons, the Nobel peace prize-winning group that was key to getting the ban treaty adopted by the United Nations in 2017, also welcomed the summit's imagery but criticized the statements coming from the leaders as "dangerous" for their lack of new proposals at a time of soaring tensions.

Praising what he saw as Kishida's "genuine" desire for progress on nuclear arms, he said that "symbolically it is important" for drawing attention to the message of peace and nuclear disarmament.

But he was unconvinced by the declaration, saying, "We can't ignore the fact that the reason Hiroshima was chosen was to carry this message of disarmament, and if it was ever a serious goal of this summit then they've fallen woefully short of that."

Ahead of the summit, Kishida's Hiroshima Action Plan, a five-pillared doctrine first outlined in his speech to the 10th NPT review conference at the United Nations in August 2022, was expected to form a central tranche of the leaders' declaration.

The plan, Kishida said at the time, is intended to back the treaty in force since 1970 to take the world from the "'reality' we face in the harsh security environment" to the "ideal of a world without nuclear weapons."

Among its actions, it calls for enhanced transparency over nuclear arms, reduced global nuclear stockpiles, encouragement of peaceful nuclear energy use and the promotion of understanding of Hiroshima and Nagasaki including through visits by world leaders.

Unlike the G-7 foreign ministers' statement released in April, which hailed the plan as "embodying a pragmatic approach given the current harsh security environment," the reference to the action plan was changed to a "welcome contribution" and "realistic, pragmatic and responsible approach."

The shift in language, Hogsta said, led to him to think "Kishida would be quite disappointed with this statement, the Hiroshima Action Plan which he announced at the NPT Review Conference last year is barely mentioned...It appears that even that plan was too much for the G-7 leaders to commit to."

Referring to the history of nuclear disarmament and rising tensions, Hogsta pointed to the formulation of the nonproliferation treaty going into force in 1970 following moves to disarm in the eight years after the Cuban missile crisis nearly brought Russia and the United States into nuclear conflict as a precedent for bold action.

But Tosaki was less convinced by calls for radical action to recognize the ban treaty.

"Japan is at the forefront of threats from Russia, China and North Korea, and is therefore compelled to rely on protection under the American nuclear umbrella," he said.

"Without some comprehensive change in the security environment, Japan cannot participate in the treaty."

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