Eighty years ago, on Aug. 6, 1945, the world changed forever when the United States exploded the first atomic bomb, “Little Boy”, over Hiroshima. In an instant, incineration ravaged the city, killing over 140,000 people. Three days later, the “Fat Man” bomb dropped on Nagasaki, killing another 75,000. By year’s end, an estimated 250,000 had died from the blasts, fire, and radiation poisoning.

These acts of war ruptured the moral and existential boundaries of modern civilization. While they marked the end of World War II, they also inaugurated a nuclear era defined by the doctrine of mutual assured destruction—a horrific logic that promised peace only through the threat of total annihilation.

The cities destroyed were not abstract military targets. Hiroshima was a cultural hub with universities, hospitals, and schools. On that August morning, thousands of civilians—including children on their way to class—were vaporized or burned alive. The bombs not only ended a war but launched a new kind of existential dread.

Many scientists who helped create the bomb later came to question its use and consequences. Joseph Rotblat, a physicist at Los Alamos where the A-bomb was constructed and assembled, resigned from the Manhattan Project when it became clear that Nazi Germany would not build a bomb. Philip Morrison, instrumental in bomb development, later became a fierce advocate for disarmament. These voices underscored a moral truth: scientific knowledge is not neutral—it comes with consequence and responsibility.

The hibakusha—survivors of the atomic bombings—became the conscience of the nuclear age. But in August 1945, a U.S. War Department censorship order suppressed photos showing the carnage—burned bodies, carbonized children, and keloid-scarred survivors. It wasn’t until 1952, when Life magazine published two of Japanese photographer Yoshito Matsushige’s five surviving images, that the American public glimpsed the true horror. Today, the hibakusha’s testimony continues to bear witness—warnings ignored amid new hypersonic missiles and AI’s creeping integration into nuclear command and control systems.

In the decades following the bombings, global efforts sought to contain the nuclear threat. The 1963 Limited Test Ban Treaty banned nuclear testing in the atmosphere, space, and underwater. The 1970 Nuclear Non-Proliferation Treaty (NPT) aimed to halt the spread of nuclear weapons and promote disarmament. Yet these efforts have proven insufficient.

Roughly 12,000 nuclear warheads remain in existence today. Thousands are on high alert—ready to launch in minutes. Nations continue modernizing arsenals, while new actors seek nuclear capabilities, raising the specter of miscalculation or accidental escalation. Nuclear infrastructure has itself become a strategic target—seen in attacks on power stations in Ukraine—and this raises chilling questions about civilian vulnerability and environmental fallout.

The United States remains one of just eight nations that have refused to ratify the Comprehensive Nuclear-Test-Ban Treaty (CTBT) of 1996. It has also declined to join the Treaty on the Prohibition of Nuclear Weapons (TPNW), which entered into force in 2021 and outright bans development, possession, and use of nuclear arms. Critics say such treaties are symbolic—but in an age of hair-trigger weapons and new nuclear states, symbolism matters.

Civil society has not remained silent. The International Campaign to Abolish Nuclear Weapons (ICAN) won the Nobel Peace Prize in 2017 for its advocacy, and grassroots movements across the globe continue to demand disarmament. These voices recall the early warnings of scientists like Rotblat, Morrison, and Albert Einstein, who famously said: “The unleashed power of the atom has changed everything save our modes of thinking.”

The Bulletin of the Atomic Scientists, which has tracked existential risk for decades, recently set its Doomsday Clock to 89 seconds to midnight—the closest in its history. As arms control erodes, and as nations bomb nuclear infrastructure and tinker with autonomous weapons, the nuclear peril expands. 

When doing research at the National Archives at Chicago, I was allowed to touch and photograph the Chianti bottle, adorned with signatures of those present, that was opened and consumed in celebration when the Italian Fermi’s uranium-and-graphite pile went critical. The specter of nuclear war hovering over humankind does not allow putting such a climactic discovery back in the bottle.

Eighty years on, we must ask: will we continue to live under the shadow of annihilation? Or will we finally act with the courage and urgency required to avoid nuclear catastrophe?