Today in 1945, the first atomic bomb used in wartime was dropped on the city of Hiroshima in Japan. Three days later, the second such device used in wartime was dropped on the city of Nagasaki. We discussed these bombings early in the history of this podcast, and so I will not repeat the details here. What I'd like to discuss is the ongoing debate over whether or not the use of nuclear weapons against two Japanese cities was justified.
The most important aspect of the debate is probably the death toll from the two bombs. Estimates vary due to poor communications and confusion in the target cities, plus the fact that some victims lived for years before succumbing to the effects of exposure to harmful amounts of radiation. Despite this, most official estimates put the number around 150,000 for both cities. Most of the dead were civilians. Keep in mind that the firebombing of Tokyo in March, 1945 killed 73,000 people, so this number of deaths in two large cities, while horrifying to imagine, was not beyond the capability of conventional strategic bombing.
President Harry S. Truman, who ultimately made the decision to use the devices against Japan, knew nothing about the existence of nuclear weapons until after President Franklin Roosevelt's death in April, 1945. The top secret Manhattan Project had been working on developing an atomic bomb since 1942; at the time, it was the largest and most expensive research and development program ever undertaken. More than 130,000 people worked on project, which produced a working bomb for testing in July, 1945; the two bombs dropped on Japan were actually the second and third weapons produced.
Truman ordered his Secretary of War, Henry Stimson, to convene a committee of scientists and prominent civilians to advise the President on the ramifications of using atomic weapons. At the end of May, 1945, the committee released its conclusions and opinions. Part of the group supported the use of the weapons, while others supported their use against military targets only. A third contingent called for a demonstration of the weapon in a desolate part of the Japan so that government could see the destructive force that was arrayed against them. This third option was dismissed over fears that if the bomb was a dud (a real possibility in early nuclear weapon construction), it could strengthen Japanese resolve. In the end, Truman decided to use the nuclear option in the hope that it would bring a swift end to the war.
The President felt justified in his desire to end the war quickly because of the carnage that loomed on the horizon. As Truman considered his decision, military leaders were drawing up plans for Operation Downfall, the invasion of the Japanese home islands. The invasion was slated to occur in two stages: Operation Olympic, the invasion of Kyushu, the southernmost of the home islands and Operation Coronet, the invasion of the area around Tokyo and Yokohama. Olympic was set to go on November 1, 1945 with Coronet following in the spring of 1946. The logistics of the invasion were staggering. The Allied naval armada would be the largest in history: 42 aircraft carriers, 24 battleships, and 400 destroyers. This did not count supply ships, landing craft and smaller vessels. 14 Army divisions, including a Commonwealth Corps from Britain, Australia and Canada, were slated to be used in the initial landing on Kyushu. The two landings would also include the entire United States Marine Corps. The President was told by his advisors to expect more than 1 million American casualties during the campaign, more than twice the number of casualties experienced by the United States in the war up to that point. While the American public had been supportive of the war to this point, one has to wonder if that support would have held up under such horrific losses.
Postwar interviews of Japanese military and government leaders revealed a plan to mobilize the civilian population, including women and children, for the fight against the invasion forces. In fact, the training for the "Patriotic Citizens Fighting Corps" had already begun. Assuming the civilian population of Kyushu and the Tokyo area would have fought, the Japanese casualties could easily have been 3 million or more.
It has been said that all wars are crimes. To an extent, this is true. War represents a failure of diplomacy. When the civil state between nations is washed away, what remains is war, which can be seen as a series of choices among evils. President Truman and his advisors stood by their decision to use nuclear weapons against two Japanese cities by claiming that they brought the war to a speedy conclusion, saving possibly millions of lives. Is this the case? Most likely yes, but some historians argue that Japan was on the verge of surrender by August, 1945, just not the unconditional surrender demanded by the Allies. The government in Tokyo was sending peace feelers to Moscow, but how serious this attempt was remains in doubt.
Some modern scholars have theorized that the bombings were meant to send a message to the Soviet Union that aggression in Europe could be devastating to Communist interests. The Red Army had already invaded the islands north of the Japanese home islands, and so the theory also suggests that the two atomic bombs were used to shorten the war before the Soviets conquered half of Japan, creating a divided nation as seen in Germany and Korea.
We have more than 60 years of hindsight on our side now; knowing what we know, it is all but impossible to place oneself in the mind of the decision makers during the summer of 1945. We will never know what an alternate course of action that August would have meant, but the fact that no nuclear weapons have been used in warfare since 1945 speaks volumes about the impression the bombing of Hiroshima and Nagasaki left on the world.