8:15 AM, 6 August 1945
At 8:15 in the morning on 6 August 1945, a single bomb dropped from the American B-29 bomber Enola Gay detonated approximately 580 metres above the centre of Hiroshima, Japan. The explosion released energy equivalent to 15,000 tonnes of TNT, created a fireball reaching temperatures of several million degrees Celsius, generated a shockwave that flattened nearly everything within a two-kilometre radius, and produced a firestorm that consumed most of what remained. In seconds, a functioning city of 350,000 people became an almost unrecognisable wasteland.
The Decision
The decision to use atomic weapons was made by President Harry S. Truman and remains one of the most debated decisions in modern history. The official justification was that an invasion of the Japanese mainland — Operation Downfall, planned for November 1945 — would cost an estimated 250,000 to over a million American casualties and millions of Japanese lives. Critics have argued that Japan was already effectively defeated and seeking terms, that the bombings were primarily intended to end the war before the Soviet Union could establish a presence in the Pacific, and that the deliberate targeting of civilian populations constituted a war crime.
The Human Cost
Estimates of the immediate death toll at Hiroshima range from 70,000 to 80,000, with total deaths by the end of 1945 — including those who died of radiation sickness — estimated between 90,000 and 140,000. Three days later, a second bomb fell on Nagasaki, killing a further 40,000 to 80,000 people. Japan surrendered on 15 August 1945.
The Nuclear Age
Hiroshima inaugurated the nuclear age — a period in which humanity possessed the means of its own complete destruction for the first time. The Cold War arms race that followed produced tens of thousands of nuclear weapons between the United States and Soviet Union. The doctrine of Mutually Assured Destruction — the understanding that nuclear war would result in the annihilation of both sides — became the central logic of international relations for 45 years. The bombing of Hiroshima is why nuclear weapons have not been used in warfare since.
