By Brad Lendon

(CNN) — As the world marks the 80th anniversary of the first use of a nuclear weapon, on the Japanese city of Hiroshima near the end of World War II, the planet is closer to seeing them used again than it has been in decades, experts and survivors are warning.

At the Hiroshima Peace Memorial Park on Wednesday morning, dignitaries and the dwindling number of survivors were set to commemorate the moment a US B-29 bomber dropped the atomic weapon known as “Little Boy” on August 6, 1945. Three days later, the nearby city of Nagasaki was destroyed by a second US atomic bomb.

More than 110,000 were killed instantly in the attacks, while hundreds of thousands more perished from injuries and radiation-related illness over the years.

To this day they remain the only times that nuclear weapons have been used in warfare. And yet these weapons continue to present a very present-day threat.

“The divisions within the international community over nuclear disarmament are deepening, and the current security environment is growing increasingly severe,” Japanese Prime Minister Shigeru Ishiba said Wednesday.

“We don’t have much time left, while we face greater nuclear threat than ever,” Nihon Hidankyo, a Japanese grassroots organization of survivors that won the Nobel Peace Prize last year for its pursuit of nuclear abolition, said in a statement ahead of the ceremony. “Our biggest challenge now is to change nuclear weapons states that give us cold shoulders even just a little.”

Contemporary tensions have been reflected in just the past week, with nuclear saber-rattling between Russia and the United States over Moscow’s invasion of Ukraine. And recent months have seen the US strike Iranian nuclear facilities with its powerful conventional bombs in a bid to stop Tehran’s nuclear program.

Earlier in the year, nuclear powers India and Pakistan fought a brief conflict over the long-running issue of control of Kashmir, prompting world leaders to scramble and avoid a dangerous escalation between the two.

“We see a clear trend of growing nuclear arsenals, sharpened nuclear rhetoric and the abandonment of arms control agreements,” Hans Kristensen, associate senior fellow with the Stockholm International Peace Research Institute’s (SIPRI) Weapons of Mass Destruction Program, said in June.

The alarming nuclear trends played a large role in the Bulletin of the Atomic Scientists earlier this year moving their “Doomsday Clock,” founded in 1947, closer than ever to a planet-wide catastrophe, 89 seconds to midnight.

The clock moved only one second from 90 seconds in 2024, but the 2025 report says the small difference should not be reason to celebrate.

“Because the world is already perilously close to the precipice, a move of even a single second should be taken as an indication of extreme danger and an unmistakable warning that every second of delay in reversing course increases the probability of global disaster,” a press release on the move said.

The group also considers climate change, biological threats like pandemics and bioweapons, and “disruptive technologies,” for instance, nefarious use of artificial intelligence, when setting the clock.

But the nuclear threat was front and center of their report released at the end of January.

“The countries that possess nuclear weapons are increasing the size and role of their arsenals, investing hundreds of billions of dollars in weapons that can destroy civilization,” the Doomsday Clock report said.

Global stockpile

The Hiroshima atomic bomb, with an explosive yield of 15 kilotons, would be considered a low-yield nuclear weapon by today’s standards. The largest nuclear weapon in the US arsenal has a yield of 1.2 megatons, 80 times greater than the Hiroshima bomb.

A single modern nuclear weapon, if exploded over a large city, could kill millions instantly, experts warn.

And there are more than 12,000 total in the hands of nine nuclear powers – the US, Russia, China, France, the United Kingdom, India, Pakistan, North Korea and Israel – according to SIPRI.

Nearly all of those countries “continued intensive nuclear modernization programs in 2024, upgrading existing weapons and adding newer versions,” SIPRI’s latest annual report said.

The US and Russia combined hold about 90% of the world’s nuclear weapons, but smaller nuclear powers are growing or planning to grow their arsenals, according to the report.

China has been at the forefront of growth, adding about 100 nuclear warheads a year, a trend the SIPRI said it expects to continue.

India is thought to be adding to its stockpile, and the UK is expected to soon, the report said.

Meanwhile, North Korea shows no sign of backing off its nuclear status, with Kim Yo Jong, the powerful sister of leader Kim Jong Un, saying last month that Pyongyang won’t give up its warheads in exchange for talks with Washington and Seoul.

“Any attempt to deny the position of the DPRK as a nuclear weapons state … will be thoroughly rejected,” she said, using the initials of the Democratic People’s Republic of Korea, the country’s formal name.

The-CNN-Wire
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