Prime Minister Fumio Kishida already had a furrowed brow before the Group of Seven summit started.

Standing on the cusp of what he hoped would be a diplomatic coup to define his administration, Kishida wasn’t leaving anything to chance.

So right up until almost the last minute, negotiations went back and forth about the planned May 19 visit by world leaders to the Hiroshima Peace Memorial Museum and the surprise presence of Ukrainian President Volodymyr Zelenskyy at the summit.

Kishida refused to take “no” for an answer as he fussed over whether bureaucrats had done enough to make sure the G-7 leaders would grasp the immensity of what unfolded on Aug. 6, 1945, the day the world’s first atomic bomb detonated over Hiroshima, killing tens of thousands of people.

Bureaucrats lost count of the number of times they liaised with their counterparts from the G-7 nations and went back to Kishida, who always barked: more.

The most cautious stance was taken, perhaps not surprisingly, by the United States, which dropped the bomb.

U.S. officials contended that President Barack Obama’s historic visit to the museum in 2016 should serve as a reference point for what would take place on May 19.

Obama was the first sitting U.S. president to visit Hiroshima. Even so, he rushed through his visit to the museum, spending only about 10 minutes on the first floor of the east wing and then leaving.

U.S. officials were demanding changes in the itinerary for President Joe Biden until the very last minute, leading Kishida to ask his subordinates, “With all the G-7 leaders viewing the displays, could we let only Biden do something different?”

In the event, Biden was the last G-7 leader to show up at the museum on the morning of May 19. Kishida thanked the assembled leaders, explained what exhibits he wanted them to see and led the group to the escalator taking them to the third floor of the east wing.

Personal belongings of the victims of the atomic bombing, as well as photos of the aftermath, are mainly displayed in the main wing, but time constraints limited the G-7 leaders to the east wing. Anticipating this eventuality, some items normally displayed in the main wing were moved to the east wing for the leaders to view.

Kishida gave a running commentary on the exhibits, explaining that he wanted them to see for themselves what the atomic bombing led to.

Among the exhibits were a burnt and bent tricycle and torn school uniforms. The leaders silently took in the displays.

Afterward, one leader expressed appreciation for having seen the displays.

At noon, the leaders exited the east wing. Forty minutes had elapsed since Kishida and Biden entered the museum.

After the visit, Kishida bragged to associates, “They viewed many more displays than Obama did, and the time they spent there was four times as long.”

One of the themes of the working dinner session was nuclear disarmament and nonproliferation.

A few leaders touched upon the morning visit to the museum. One was clearly moved by the experience, while another thanked Kishida for serving as tour guide.

When Kishida met with reporters that evening, he said the museum visit created a magic opportunity for the “G-7 leaders to take in what happened after the atomic bombing and share that moment in their hearts.”

He called it “historic from the standpoint of demonstrating to the world our resolve to work toward a world without nuclear weapons.”

But whether it was truly a historic event will depend on actual progress made toward nuclear disarmament and nonproliferation.

COULDN’T SAY NO TO UKRAINE

Japanese officials were informed through diplomatic channels in late April, before the start of the Golden Week of national holidays, that Zelenskyy was interested in coming to Hiroshima for the G-7 summit. Initially, the plan had been for him to join online.

When Foreign Ministry officials informed Kishida of the Ukrainian request, it meant starting work on a new round of headaches, such as strengthening security as well as coordinating with other participants in the summit. The officials cautioned that Zelenskyy could dominate the entire summit if he came to Hiroshima.

While Kishida acknowledged there were many matters to be handled, he also realized it would be difficult to turn down the Ukrainian president’s request.

“I will take on all the risks,” Kishida said as he instructed officials to begin coordinating with counterparts from other nations.

Obtaining the understanding of nonmember nations was crucial because some, namely India and Brazil, among others, maintain close economic ties with Russia.

“If any nation gets uptight about Zelenskyy participating directly, the summit could end up displaying only ‘division’ rather than ‘cooperation,” a high-ranking official in the prime minister’s office remarked.

Determined to avoid having the summit become a divided one, officials decided to focus on basic principles that no nation could reject: not allowing any unilateral change in the world's status quo and protecting a free and open international order based on the rule of law.

Officials briefed their counterparts in the eight non-member nations invited to Hiroshima about Zelenskyy’s direct participation and put that aspect of the matter to rest about 10 days before the start of the summit.

But coordination over security matters continued until the very last minute and thorough measures were implemented to maintain secrecy. And to avoid giving the appearance that Zelenskyy had taken over the summit, the decision was made to release the communique by the G-7 leaders on May 20, a day earlier than originally planned. Zelenskyy joined the discussions from the following day.

Kishida told associates that the agreement reached even with the participation of nations close to Russia would send a strong message to Russia and China.

He also touched upon the fact that after independence Ukraine abandoned the nuclear weapons that the Soviet Union had deployed within its borders.

“A nation that gave up its nuclear weapons has been invaded by a nation that has threatened to use nuclear weapons,” Kishida told associates. “If Russia somehow gained from its invasion that would be the worst message in the context of nuclear disarmament. That is something we must avoid.”