Hiroshima and its people have been hoping to build momentum toward a world without nuclear weapons through the Group of Seven summit in May, with its museum set to play a key role in conveying the reality of the 1945 atomic bombing of the western Japan city.

With Barack Obama famously becoming the first sitting U.S. president to visit in 2016, the Hiroshima Peace Memorial Museum is expected to welcome the leaders of the G-7 industrialized nations on the first day of the gathering, with exhibits emphasizing the bombing's human costs at a time of soaring nuclear tensions worldwide.

Prime Minister Fumio Kishida is trumpeting this year's gathering as a chance to call for a "world without nuclear weapons," and the museum's director, Takuo Takigawa, sees the visit on the summit's sidelines as constituting a "historic opportunity of greater importance and visibility" than Obama's.

Visitors to the Hiroshima Peace Memorial Museum take in some of the exhibits, in Hiroshima on April 6, 2023. (Kyodo)

The anticipated tour would be the first joint one by the G-7 nations, three of whose members -- the United States, Britain and France -- are nuclear powers for whom visits to atomic-bombed Japanese cities are potentially politically awkward.

But atomic bomb survivors, civic groups and ordinary citizens are calling for the visit to be more than a photo opportunity for the leaders in the face of the growing threat of nuclear use sparked by Russia's war in Ukraine.

Opened in 1955, the museum is intended to pass on the story of Hiroshima long after those directly affected by the bombing are gone. It holds about 100,000 items in its collection, with many of them the donated effects of people caught in the bombing, ranging from belongings such as clothing to organic matter including hair.

It completed its third renovation in 2019, aiming to give more weight to individuals' experiences of the tragedy. It welcomed a record-high 1.76 million visitors that year, including some 520,000 foreign nationals.

Its unflinching depiction of the bombing leaves strong impressions on many visitors from overseas. Among them is Ed Asmutis, a 62-year-old on a tour from the United States who said early last month he left feeling that "every elected official should take an opportunity to walk through the museum" to reflect on their future decision-making.

Visitors to the Hiroshima Peace Memorial Museum on April 6, 2023, enter a hall of images of the mushroom cloud created when the atomic bomb exploded. (Kyodo)

Takigawa says he hopes the leaders will "take the chance to reflect deeply" on the exhibits and the "reality" of the atomic bombing that devastated Hiroshima and ushered in the nuclear age at 8:15 a.m. on Aug. 6, 1945.

Among the pieces leaders are likely to see are graphic photographs of people burned and disfigured by the bomb's searing heat, and the "human shadow" left by an individual sitting on the steps of a bank at the time of the blast.

"The bombing killed a huge number of people, some 140,000 in Hiroshima by the end of 1945, and we must convey that, but each individual's grief and suffering varies," Takigawa said. "The renovated exhibition offers visitors the chance to look closely at those individual griefs and sufferings."

While Kishida, as then foreign minister, faced difficulties in realizing Obama's visit to Hiroshima seven years ago, Russia's nuclear threats in its war in Ukraine have made visits by the G-7 leaders this time much easier to arrange.

Aging atomic bomb survivors, meanwhile, are hoping that the visit will just be the start in a process of meaningful dialogue.

Hiroshima Peace Memorial Museum Director Takuo Takigawa is pictured in Hiroshima on April 6, 2023. (Kyodo)

"My simple wish is for the leaders to give at least 30 minutes, an hour, to sincerely take in the museum. The reality is much worse, but they should start discussions from there," said Kazuhiko Futagawa, organizer for the Japan In-Utero Hibakusha Network.

"The discussions should not be held just between themselves. To avoid the same things repeating, they need to speak with states like Russia, China and North Korea, too, although it will take time," he said.

At 77, Futagawa is one of the youngest survivors alive today. He was in his mother's womb when she was exposed to the bomb, and he lost his father and older sister to the attack.

At the end of March 2022, there were 118,935 legally recognized living atomic bombing survivors, known as hibakusha in Japan, with their average age standing at 84.53.

The desire for substantive engagement is not restricted to survivors, either. Yuna Okajima, an 18-year-old native of Hiroshima, and 16-year-old Miharu Obayashi from Kawasaki near Tokyo, have together launched a multilingual online petition urging the leaders to meet atomic bomb survivors and engage with the museum.

Their motivation to speak out came from reports that Obama spent just 10 minutes at the museum, which Okajima found "disrespectful to Hiroshima." By Director Takigawa's estimate, it takes a visitor about one-and-a-half hours to thoroughly take in the exhibits today.

Okajima was also concerned that by holding the summit in the city, the Japanese government might "start saying it had already laid a path to nuclear abolition" despite having a stance on international efforts to abolish nuclear weapons that has been criticized both at home and abroad for ambiguity.

Japan, which relies on U.S. nuclear deterrence for protection, backs the Nuclear Non-Proliferation Treaty, but has not signed or ratified the Treaty on the Prohibition of Nuclear Weapons, which the nuclear powers do not support.

Yuna Okajima, one of two teenagers who launched a petition calling on Group of Seven nations' leaders to visit the Hiroshima Peace Memorial Museum and to meet with atomic bomb survivors, is pictured outside the museum in Hiroshima on April 6, 2023. (Kyodo)

Kishida has defended this approach as a way for Japan, the only country to suffer a nuclear attack, to bridge the differences between nuclear and nonnuclear states.

"We do not believe that a 'commitment to peace' is just simply the G-7 leaders gathering in the atomic-bombed cities, taking pictures, and having discussions," according to material from Okajima and Obayashi's campaign.

Their petition, which will run until just before the summit, was submitted to the Foreign Ministry in March, when it had garnered around 20,000 signatures.

Despite the calls for longer visits, Takigawa said he would let individual visitors decide how to engage with the museum.

"Our role, ultimately, is to provide an opportunity for visitors to learn the truth about what happened in Hiroshima. But I hope those who come here will engage with the truth, and deepen their understanding," he said.

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