If there is one event that defines the modern world, it is the blinding, searing, radioactive explosion over the city of Hiroshima on the morning of August 6, 1945. Not many people still alive will have any memory of a world not haunted by the possibility of nuclear annihilation. That was a world of wars between major powers. Twice between 1914 and 1945, the most powerful nations mobilised all manpower and weapons at their command and fought to exhaustion.
Cities were bombed mercilessly. Civilian casualties were an accepted method of attacking the enemy's morale. The United States knew its new bomb was capable of destruction on a greater scale and believed nothing less would bring about Japan's defeat. Tokyo had been conventionally bombed to matchwood. Even after the terrible demonstration of atomic power at Hiroshima, and a second on the city of Nagasaki on August 9, Japanese would long remember their shock at hearing their Emperor surrender.
The full horror of Hiroshima and Nagasaki was soon known. Not a building was left standing, except the one at Hiroshima directly under the bomb that remains as a stark monument today. Nearby, objects tell their own story. Some stone steps have a dark human shape etched on them: all that remains of a person vaporised in that instant.
It is no wonder the world's calculations of war and power changed from that morning. The greater wonder is the immediate postwar superpowers, the United States and the Soviet Union, managed to avoid mutually assured destruction. Their 45-year Cold War was not just a contest for strategic power. It was more like a religious war in its clash of social and economic philosophy. The antagonism went deeper than rivalries that had previously pitched European powers into war, and missiles could have been launched across continents in a heated moment.
