It was 8:15 in the morning, and 13-year-old Setsuko Thurlow was at army headquarters with her classmates who had been selected to help with a decoding project. Suddenly, she saw a flash of bluish white light outside the window and felt the odd sensation of floating. A massive blast knocked her unconscious. She awoke sometime later under a heap of rubble.

“I knew I faced death,” Thurlow tells a standing-room-only audience in Toronto recently. “I began to hear my classmates’ cries: ‘Mother, help me! God, help me!’ Then, suddenly, I felt hands touching my shoulder and heard a man saying, ‘Don’t give up. Keep pushing, keep moving. . . . See the light? Crawl toward it.”

Somehow, Thurlow made her way out of the collapsed building. Although it was morning, she remembers a twilight darkness covering the sky from all of the dust and smoke. Through the haze, she could see a ghostly procession of people, carefully stepping over the dead and dying. The stunned figures “didn’t look like human beings,” Thurlow tells the crowd. “Their hair stood straight up, they were naked and bleeding, burned, blackened and swollen. Parts of their bodies were missing, flesh and skin hanging from their bones.”

The date was Aug. 6, 1945, and Thurlow was only 1.8 kilometres from ground zero when a U.S. B-29 bomber released an atomic bomb dubbed Little Boy. The explosion obliterated her home city of Hiroshima. Thurlow lost 351 schoolmates in the assault, as well as eight family members. The overall toll was much worse. At least 70,000 people are estimated to have died in the initial blast, while up to the same number died within months from radiation exposure. The total number of dead five years later is said to be around 200,000, due to cancer and other long-term effects.

Three days after the Hiroshima attack, the United States dropped another atomic bomb on the Japanese city of Nagasaki, killing as many as 80,000 people. Both were such horrific catastrophes that 73 years later, the mere mention of the cities’ names conjures up images of the devastation.

In the decades since the bombing, Thurlow has grown from victim to survivor to activist.

“I want you to feel, above and around, a great cloud of a quarter million souls. Each person had a name. Each person was loved by someone. Let us ensure that their deaths were not in vain.” —Setsuko Thurlow on Hiroshima and Nagasaki victims

It’s an evolution fuelled by one singular belief — that no one should ever endure the “massive and grotesque scale of death and suffering” caused by an atomic bomb. Today, she is 86 and has told her personal story countless times, in dozens of countries.

In sharing her experience, she has put a human face to the destructive force of nuclear weapons and made it harder for audiences to turn away. That’s been her lifetime goal: to keep talking until the world listens.

And sometimes it does, as was the case last December, when she travelled to Oslo, Norway, to receive the Nobel Peace Prize on behalf of the International Campaign to Abolish Nuclear Weapons (ICAN). The global coalition of non-governmental organizations helped lay the groundwork for the United Nations Treaty on the Prohibition of Nuclear Weapons, adopted last July. It was a major victory for Thurlow, who was instrumental in creating the treaty. “I’ve been waiting for this day for seven decades,” she said after the historic vote.

Although Thurlow has told her story around the world, tonight’s Toronto audience is special. The crowd includes students, staff and alumni from the University of Toronto’s faculty of social work, where she received her master’s degree more than 60 years ago. She has fond memories of those years and her successful career as a social worker with the Toronto YWCA and the Toronto Board of Education.

As she begins, Thurlow confesses that she forgot to finish writing her speech. Then she jokes, “But you have no choice but to listen.” The audience laughs. It is the only light moment in her talk.

For 45 minutes, she stands strong at the podium, her voice never faltering. The passage of time hasn’t lessened the emotional impact of the bombing. She tells us the horror of what she experienced has been crystallized in a single memory — the image of her four-year-old nephew, who was transformed from an innocent child into a charred, blackened and swollen chunk of flesh. He begged for water, she says, until “his death finally released him from his agony.” She stares out at the crowd. “His terrible image has come to represent my life.”

In the aftermath of the bombing, “people had to endure the physical devastation, the starvation, homelessness, total lack of health care, rapid spreading of disease,” says Thurlow. Many of those who survived the initial blast suffered deaths from radiation poisoning, which caused painful nausea and purple lesions. “In those days, we had to examine every part of our body before we got dressed to make sure there were no purple spots, to make sure we would live another day.” The dead were thrown into pits by soldiers, then doused with gasoline and set on fire.

Although the American government sent medical authorities to Japan, Thurlow says their purpose was to study the effects of radiation on human beings and not to treat the injured. “Needless to say, the survivors felt treated as guinea pigs, first as the target of the atomic bombings, then as the subject of the medical research.”

The U.S. authorities also censored newspapers to stymie media coverage of the suffering. They confiscated personal items, including diaries, telegraphs, medical records, films and haiku poetry to further stop any information from getting out, remembers Thurlow.

Canada also had a part in the atomic bomb, she tells the audience. The uranium used in the bomb was mined and transported by people near the Great Bear Lake in the Northwest Territories. “They carried sacks of radioactive uranium on their backs along rivers, rapids and portages, and many subsequently died of cancer.”

It was 1954 when Thurlow first talked publicly about nuclear weapons. She was 22 and had come to the United States on a scholarship to study at Lynchburg College in Virginia. During an interview with the local media, she freely expressed her opinions about America’s actions. She was stunned when she later received a barrage of hate mail.

“When I came to the U.S., there was a totally different perception of the bombings,” says Thurlow in an interview. “They said those bombs ended the war quickly so [their] GIs could come home sooner than expected.”

After much soul-searching, she decided she would continue to speak out. Telling her story many times hasn’t made it less difficult. People assume it comes naturally now, “but believe me, that’s not so,” she says. “To repeat some of the painful memories is not easy.”

Kathleen Sullivan, the director of Hibakusha Stories, a partner organization of ICAN dedicated to sharing the witness of atomic bomb survivors with high school and university students, recalls the first time she heard Thurlow speak 18 years ago. It was a “revelation that changed my life forever,” she says. “I will never forget that day, marvelling at this force of nature, who would remember and recount such horrific details, time and again, at the expense of her own comfort in order that others understood the risks and reality of nuclear weapons.”

Thurlow’s faith has played a large part in her ability to sustain the momentum. She was raised Buddhist and, as a child, helped in a morning ritual of placing steaming- hot rice in a special corner of the house. “We were a really devout Buddhist family, and then I spent 10 years at a Christian high school and university [in Japan],” she says. “I lived with those people, and every day we had 45-minute services.”

In the years following the bombing, people were hungry for answers and were searching for meaning in what had happened, Thurlow says. “The Christians talk about their love of God, but we [survivors] asked, ‘What kind of God is it? What God allows something like this?’ People were filled with millions of questions like that. I was, too.”

She became a Christian about four years after the Second World War. She still prays before every talk and lives by the motto of one school she attended: “We are workers together with God.” “That’s always stayed with me,” she says. “Without that kind of relationship, I certainly couldn’t have spread the word like I have.”

Becoming a Christian would also play a role in finding her life partner. In her third year of university in Japan, she took part in an educational experience for young Christians at Kwansei Gakuin, a United Church-affiliated school not far from Osaka. Some 30 students from universities around the world lived in a shinto shrine for the summer.

That’s where she met Jim Thurlow, a young man from St. Thomas, Ont., who was teaching history there. They began dating and married two years later in 1955. Setsuko was then 23 and in the graduate social work program at U of T. The couple lived in Toronto for two years before moving back to Japan, where they both worked at Kwansei Gakuin. In 1962, with two sons in tow, aged one and three, they returned to Toronto on sabbatical. After a short time, they decided to stay. Jim became a high school history teacher, while Setsuko pursued her career in social work. They attended a number of United churches over the years but came away disappointed. Most were more interested in raising money than in social activism, Setsuko says.

Thurlow regards Jim, who died in 2011, as her “soulmate.” Throughout their life together, he was a huge support, helping with everything from organizing events to founding anti-nuclear groups. In 2007, she became involved with ICAN and took part in negotiations toward an international agreement banning nuclear arms. The group’s efforts paid off last summer, when 122 countries — almost two-thirds of the total United Nations membership — moved to adopt the UN Treaty on the Prohibition of Nuclear Weapons. Thurlow was present for the vote and describes it as “the greatest reward.” Five months later, she and Beatrice Fihn, ICAN’s executive director, accepted the Nobel Peace Prize on behalf of the organization.

“Today, I want you to feel in this hall the presence of all those who perished in Hiroshima and Nagasaki,” Thurlow told the audience at the Nobel ceremony. “I want you to feel, above and around, a great cloud of a quarter million souls. Each person had a name. Each person was loved by someone. Let us ensure that their deaths were not in vain.”

While Thurlow says the Nobel “belongs to everyone” who has campaigned against nuclear weapons, her fellow activists laud her dedication to the cause. Ray Acheson, director of the disarmament program of the Women’s International League for Peace and Freedom, another ICAN partner, describes Thurlow as a powerful presence in the anti-nuclear movement. “Her commitment to the pursuit of nuclear abolition is unparalleled. She provides a voice of reason, experience and purpose that few others could hope to emulate.” Thurlow’s story has inspired hundreds of thousands of people, adds Kathleen Sullivan. “Future generations will say her name in gratitude.”

“The Christians talk about their love of God, but we [survivors] asked, ‘What kind of God is it? What God allows something like this?’”

Soon after the attacks in Hiroshima and Nagasaki, the Japanese surrendered, bringing about the end of the Second World War. Many westerners at the time believed the bombings were necessary; however, over the years, many more have questioned whether the costs in both human lives and on the environment were too high.

A Gallup poll taken in 1945 right after the bombings showed that 85 percent of Americans approved of using atomic weapons on Japanese cities. By comparison, a 2015 survey by the Pew Research Center found that only 56 percent of Americans believed the use of nuclear weapons was justified. The numbers may be shifting because people now recognize that the horror of an atomic bombing can linger for decades due to the genetically damaging radioactive fallout.

Despite the deadly consequences of atomic war, nine countries still possess over 14,000 nuclear weapons. Leading the way are the United States and Russia, who together have about 1,800 of their nuclear weapons on high-alert status, which means they are ready to be launched within minutes, according to ICAN. Most of those bombs are more powerful than the ones dropped on Japan in 1945, and the strongest could kill millions of people with a single nuclear warhead.

And while 122 nations voted to adopt the UN treaty, only 10 have actually ratified the agreement so far (it will come into force when 50 countries approve it). Thurlow was deeply disappointed when Canadian Prime Minister Justin Trudeau refused to participate. She does not accept the claim that America’s nuclear weapons are essential for deterrence.

Despite the lack of support for the UN treaty from Canada and its NATO allies, Thurlow tells the audience at her U of T talk that she is more optimistic than ever about the future. “I have never felt as hopeful as I do now because I see the countless younger activists, so bright, energetic, creative and politically savvy.”

She herself has no plans to stop. Tonight, she ends her speech like she has done many times before — with a plea for people to get involved. Contact your representative, she says. Tell them that Canada must reverse its decision and sign the UN treaty. “We must seize this opportunity and make this work for us and for the world,” Thurlow urges. “I would like to know that my time here has been well spent.”

This piece first appeared in the July/August 2018 issue of The Observer under the headline ‘No human being should ever have to repeat our experience.’’