Sixty-two years later, the memory of the atomic bombing of Hiroshima still holds such a grip on Japan that its defense minister has had to resign simply for suggesting the attack was "unavoidable."
Now, in a sign of changing times, the task of spreading Hiroshima's message to the world has been entrusted to an American, a citizen of the country that dropped the bomb on Aug. 6, 1945.
Today's anniversary comes just a month after Fumio Kyuma was forced to quit as defense minister for seeming to implying that the bombing was inevitable, because otherwise Japan would have gone on fighting and would have lost territory to a Soviet invasion.
Not so, says Steven Leeper, the first American to head the Hiroshima Peace and Culture Foundation.
"Historically, that's not correct," he said in an interview, "And it's unbelievable that he said it."
Leeper shares the view of most Japanese: that Japan had already lost the war and that the bombing of Hiroshima, and of Nagasaki three days later, was wrong and unnecessary.
"Everybody knows on the left and the right that Japan was finished at the time the bomb was dropped," Leeper said.
Historically, the US justification was that the bombing ended the war and limited the number of US military and Japanese civilian lives that would have been lost in a land invasion.
The Japanese perspective argues that Japan was already working on negotiating a peace treaty, as well as a surrender, and that the US dropped the bomb to test its destructive power and to intimidate the Soviet Union.
Leeper says that rather than focus on fixing blame, Hiroshima will work to educate people in other countries about the effects of nuclear weapons.
The Illinois-born American, now 59, has lived in both countries and says he became interested in disarmament issues when his translation company worked with bomb survivors.
In 1999, he created the Global Peacemakers Association in Hiroshima, an organization that trains youth and elderly to travel abroad and speak about the bombings in Japanese and English.
Leeper says his appointment by Hiroshima Mayor Tadatoshi Akiba has been largely supported because he can bridge the language gap and foster a more "cosmopolitan" Hiroshima.
"There have been some people outside Hiroshima who have written letters complaining after my appointment got into the national press. But really very few," he said. "By far, it's mostly enthusiastic praise of the mayor for putting me here, and taking such a bold step."
His group has offered to send exhibits of survivor testimonies, films, and educational posters to libraries, universities and museums across the US.
Leeper said he will also use his translation know-how to build nuclear weapons education programs in English and encourage relationships with international peace organizations.
He is working against time, noting that as time passes the number of survivors is dwindling and their largest organization "disbanded for lack of people."
"The survivors who are really healthy or active are mostly the ones who were very young children, or came into town later, so we don't have nearly as many who were right there to feel the blast," he said. "It's a problem for us."
When school groups tour the peace park built on the wreckage of midtown Hiroshima, they are often led by bomb survivors. The city has collected photos, stories and video memories from over 118,000 survivors.