The nuclear arms race is heating up. Will it take another bomb to renew the push for disarmament?

Eighty years after the first atomic bombs fell, experts and survivors warn that the horrors of Hiroshima and Nagasaki could once again be unleashed, as the nuclear arms race heats up.

"Most experts believe that the risk of nuclear use is rising, and in some cases rising dramatically," said Joseph Cirincione, a national security analyst who has worked on nuclear non-proliferation for decades.

"The same drivers that we saw in the '50s and '60s that fuelled the arms race are now reasserting themselves … and we don't have the public pressure to counter them," he told The Sunday Magazine.

In January, the Bulletin of Atomic Scientists updated its Doomsday Clock to read 89 seconds to midnight, where 12:00 represents the moment of humanity's destruction. The organization considered factors like climate change and advances in AI, but also highlighted conflict in the Middle East and the potential for nuclear escalation in Russia's invasion of Ukraine.

Cirincione said that all nine nations with nuclear weapons — the U.S., Russia, the U.K., France, China, India, Pakistan, Israel and North Korea — are currently increasing or modernizing their arsenals or delivery systems. He added that France is considering extending its nuclear umbrella over other EU nations, increasing the scope of deterrence but also potential conflict. And countries like South Korea are considering building their own weapons for the first time, fearing that they can no longer rely on the U.S. for protection.

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In June, Israel and the U.S. targeted Iranian nuclear and military sites, resulting in a 12-day conflict. On Friday, U.S. President Donald Trump ordered two nuclear submarines to be moved in response to "inflammatory statements" from former Russian president Dmitry Medvedev.

All of this comes after "a good 40 years of reductions in nuclear arsenals," Cirincione said, adding that it has always taken "public pressure to move the politicians in the right direction."

He says he thinks that public pressure is absent today because people took for granted the trend toward disarmament and began to focus on other pressing issues, like climate change.

He said that among some experts and campaigners, there is now a feeling of pessimism that it might take the unthinkable to renew the disarmament push.

"The view is basically we may need to see a nuclear detonation before the public's alerted to the threat and motivated to mobilize," he said.

"Some fear we may need to go through the horror of seeing them being used."

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Japanese Canadian Setsuko Thurlow was 13 and living in Hiroshima on Aug. 6, 1945, when the U.S. detonated an atomic bomb over the quarter of a million people who lived there.

She says she remembers a blinding flash of light, and then felt like she was floating. When she crawled out from under a collapsing building, everything around her was rubble and flame.

"My beloved city just flattened and burned with one bomb. And 351 schoolmates, they were all burned to death, alive," she said.

She remembers her four-year-old nephew "transformed into a melted chunk of flesh."

Three days later, a second nuclear bomb was detonated over the Japanese city of Nagasaki. The two blasts combined killed approximately 120,000 people instantly and tens of thousands more in the years that followed. Japan's surrender was announced on Aug. 15, bringing an end to the Second World War.

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Thurlow, who is 93, married a Canadian in 1950 and now lives in Toronto. She has worked for decades as a campaigner against nuclear weapons and was awarded the Nobel Peace Prize in 2017 for her work with the International Campaign to Abolish Nuclear Weapons.

Author and journalist Garrett Graff said this year's 80th anniversary is "especially poignant" for many people, because so few survivors of Hiroshima and Nagasaki remain.

"I think it is up to us to carry forward their vision and dream of ensuring that … this remains the last and only time we use nuclear weapons," said Graff, author of The Devil Reached Toward the Sky: An Oral History of the Making and Unleashing of the Atomic Bomb.

Thurlow shares the concerns that another nuclear strike could be "getting closer and closer," and says Canada isn't doing enough to push back on nuclear proliferation, despite polls showing that a majority of Canadians want nuclear weapons eliminated.

"I have had serious concern that the government has not been responding to the will of the people," she said, adding that she wants to see Canada regain its "worldwide respect and reputation as a peace builder."

The Sunday Magazine contacted the Canadian Nuclear Safety Commission to ask what Canada is doing about the global proliferation of nuclear arms, but was referred to Global Affairs Canada. GAC did not respond to a request for comment by deadline.

Cirincione said in the 1980s, millions of people around the world took part in demonstrations against nuclear weapons. He says he thinks the push for disarmament could be revived if it can be merged with other movements for change.

"You want to increase health care, you want to increase education? Where are you gonna get the money?" he said.

The answer might lie in high global spending on nuclear weapons, he said, "that could provide a big source of the money you need for human needs, not human destruction."