199 The Bombing of Hiroshima and Nagasaki
31.7.6: The Bombing of Hiroshima and Nagasaki
On August 6, 1945, the United States dropped an atomic bomb on the Japanese city of Hiroshima in the first nuclear attack in history. Three days later, on August 9, the U.S. dropped another atomic bomb on Nagasaki, the last nuclear attack in history.
Learning Objective
Analyze the decision to drop the atomic bombs
Key Points
- In the final year of the war, the Allies prepared for what was anticipated to be a very costly invasion of the Japanese mainland, with estimates of half a million casualties on both sides.
- At the Potsdam Conference, the Allies called for the unconditional surrender of the Japanese armed forces, with the alternative being “prompt and utter destruction.” The Japanese ignored this ultimatum, prompting the American government to plan a nuclear attack.
- On August 6, the U.S. dropped a uranium gun-type atomic bomb (Little Boy) on Hiroshima.
- American President Harry S. Truman called for Japan’s surrender 16 hours later, warning them to “expect a rain of ruin from the air, the like of which has never been seen on this earth,” an ultimatum that was again ignored by the Japanese, who planned to continue fighting.
- Three days later, on August 9, the U.S. dropped a plutonium implosion-type bomb (Fat Man) on Nagasaki.
- Within the first two to four months of the bombings, the acute effects of the atomic bombings killed 90,000-146,000 people in Hiroshima and 39,000-80,000 in Nagasaki; roughly half of the deaths in each city occurred on the first day.
- On August 15, six days after the bombing of Nagasaki and the Soviet Union’s declaration of war, Japan announced its surrender to the Allies.
- The bombings’ role in Japan’s surrender and their ethical justification are still debated by historians and other scholars.
Key Terms
- Manhattan Project
- A research and development project that produced the first nuclear weapons during World War II.
- atomic bomb
- A nuclear weapon that derives its explosive energy from nuclear fission reactions.
- Operation Downfall
- The code name for the Allied plan for the invasion of Japan near the end of World War II.
Overview
The United States, with the consent of the United Kingdom as laid down in the Quebec Agreement, dropped nuclear weapons on the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945, during the final stage of World War II. The two bombings, which killed at least 129,000 people, remain the only use of nuclear weapons for warfare in history.
In the final year of the war, the Allies prepared for what was anticipated to be a very costly invasion of the Japanese mainland. This was preceded by a U.S. firebombing campaign that destroyed 67 Japanese cities. The war in Europe concluded when Nazi Germany signed its instrument of surrender on May 8, 1945. The Japanese, facing the same fate, refused to accept the Allies’ demands for unconditional surrender and the Pacific War continued. Togethe