Nuclear security

In the 75 years since Hiroshima, nuclear testing killed untold thousands

On Aug. 6, 1945, the United States dropped an atomic bomb on Hiroshima that obliterated much of the city and sent a mushroom cloud tens of thousands of feet into the air. After 75 years, it continues to cast a shadow over world affairs.

The bombing of Nagasaki three days later was the second and final time the atomic bomb saw use in war. On Aug. 15, Japan announced its surrender.

The weapons caused unparalleled destruction, snuffing out more than 150,000 lives. But those were not the last people to die as a result of nuclear detonations.

In the decades since 1945, the United States, the Soviet Union and at least six other countries set off a total of more than 2,000 nuclear test explosions, which caused tens of thousands of deaths around the world, according to some estimates, along with displacement and environmental degradation that long remained secret and continue to affect communities today.