People walk under a banner in a shopping street, announcing the upcoming Group of Seven nations' meetings in Hiroshima, western Japan on May 17, 2023. The G7 Summit starts May 19, 2023. As leaders of the G7 nations gather in the Japanese city this week for a summit, Japanese Prime Minister Fumio Kishida wants a pledge on nuclear disarmament. (PHOTO / AP)

HIROSHIMA, Japan – The last time a US president visited Hiroshima, atomic bomb survivor Shigeaki Mori was filled with hope for a future without nuclear weapons. Seven years later, he's more skeptical.

As leaders of the Group of Seven (G7) nations gather in the Japanese city this week for a summit, Prime Minister Fumio Kishida wants a pledge on nuclear disarmament.

Japanese Prime Minister Fumio Kishida, long on the dovish wing on Japan's ruling party, delivered the biggest defense spending increase in Japan's post-war history last year

Kishida, who represents Hiroshima, said he chose it for the summit to focus attention on nuclear weapons. But the venue has also highlighted a significant shift in global security since 2016, when Barack Obama became the first incumbent US president to visit.

Many of Japan's "hibakusha" – atomic bomb victims whose average age is 85 – worry the summit may be a final chance to call for disarmament. They fear Hiroshima's legacy – its importance as the first city to be flattened by a nuclear weapon – may be reduced to a historical artifact rather than a call for change.

"I want to see the leaders commit to getting rid of nuclear weapons," Mori, 86, said in an interview. "I also know it's very hard to get them to go that far."

Kishida, long on the dovish wing on Japan's ruling party, delivered the biggest defense spending increase in Japan's post-war history last year.

Some 51 percent Japanese supported an increase in the defense budget, and 55 percent agreed on the need for counter-strike capabilities, according to a poll by broadcaster NHK in December

Japan gave up the right to wage war after World War Two and maintains self-defense forces. It relies on the United States for protection.

Japanese are more likely aware they have to tolerate a "nuclear umbrella," said Noriyuki Kawano, head of Hiroshima University's Center for Peace.

"The ideal of a nuclear-free world and the reality of living under a nuclear umbrella coexist," he said.

"There is still a coexistence, but we might be seeing a tip in those scales now" towards a more pragmatic view, he said.

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Some 51 percent Japanese supported an increase in the defense budget, and 55 percent agreed on the need for counter-strike capabilities, according to a poll by broadcaster NHK in December.

Knocked unconscious

Mori, eight years old when the bomb hit on the morning of August 6, 1945, was knocked unconscious by the blast. When he came to, he saw a crouched woman holding her own entrails asking for the nearest hospital.

Thirty years later he began a multi-decade quest to find how many victims were cremated at his school playground. His work also unearthed the identities of 12 Americans who died in the bombing.

Obama spoke of the "shared responsibility to look directly in the eye of history" when he visited Hiroshima, and praised Mori's work in his speech.

Senior German government sources did not list nuclear disarmament as a high priority, saying at the G7 it was "important mainly for Japan"

The moment of Mori being embraced by Obama at the bomb site became the defining image of the visit. Obama avoided any direct expression of remorse or apology for the bombings, something many Japanese feel is overdue.

"I just don't want all of this to end up being a dream," Mori said of his hopes for disarmament.

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President Joe Biden is unlikely to deliver an independent message on disarmament during the summit, US officials said, although he will visit the site.

A US official said Washington was not pushing an independent agenda on the issue, adding Japan was leading discussions.

Senior German government sources did not list nuclear disarmament as a high priority, saying at the G7 it was "important mainly for Japan".

Delicate balance

One senior European G7 source described the delicate balance between a desire for eventual disarmament and the reality of security.

"The final objective is a world without nuclear weapons, but also we can't be naive and disarm today knowing that we are more than ever dependent" on deterrence, the source told Reuters.

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Elderly hibakusha often talk about seeing a world free of nuclear arms, said survivor Masashi Ieshima, who now lives in Tokyo.

"But to be honest there's a despair behind the brave faces we put on too, that we may not get to see that during our lifetimes," he said.

Without real change, Hiroshima risked becoming just a publicity platform for Kishida, he said.

"Then what's the point of doing this in Hiroshima at all?"