Bombings of Hiroshima and Nagasaki

Prior to World War Two, scientists in Nazi Germany began organizing atomic investigation. American scientists, many of who were refugees, began getting worried about this. In 1940, America established its own atomic research. After many years of research, scientists began developing substances for nuclear fission, uranium-235, and plutonium. They sent these new substances to Los Alamos, New Mexico. J. Robert Oppenheimer was the leader of a team set to turn these materials into a bomb.

The Interim Committee was a highly confidential group of men who met to discuss matters of the atomic bomb.

They now had the decision to make, as to which city was the bomb should be used for. The committee of scientists and Army air force officers met in late May 1945, to discuss this topic. They named Kyoto, Hiroshima, Niigata, and Kokura arsenal as the most ideal targets. Stimson removed Kyoto, as it was Japan’s most adored cultural center, and replaced it with Nagasaki. Nagasaki had a large military base, but many valleys and hills making it one of the last on the list.

Now all they had to wait for was Truman’s official confirmation and the weather’s allowance to get ready for the bombing.

While the bomb was being made, there were many debates over how it was to be used. The Interim Committee met on June 21, 1945. Some argued that the bomb should be demonstrated on uninhabited land and said that it would be enough to get Japan to surrender. Some said that the bomb should be used on a large city without warning.

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The final decision was for the bomb to be used as soon as possible, on a city, without a previous demonstration, and without warning.

Many would remain skeptical about the bomb’s efficiency until the bomb was able to be tested. This test would be the first atomic explosion ever known, so estimates of the bomb’s power differed greatly. Some scientists still had their personal doubts if the bomb would even work. Most pieces of the bomb were transported to Alamogordo, New Mexico on July 14, 1945.

The location chosen for the test was an isolated corner of the Alamogordo Bombing Range, 210 miles south of Los Alamos. It was also known as the “Jornada del Muerto,” or “Journey of Death”. Robert Oppenheimer named this test the “Trinity” Test after poems written by John Donne. The Trinity Test was planned for the duration of May and June and was ready by the beginning of July 1945. Three observation shelters were set up 10,000 yards to the west, south, and north of ground zero. Scientists were to hide out in these bunkers and observe and measure the energy and other important aspects of the explosion. Further measurements would be done to calculate damage estimates and to document the behavior of the fire cloud.

Scientists were most concerned with the radiation the bomb could release. The army was ready to evacuate people in nearby areas if needed. The bomb was ready to be tested on July 13, 1945. Scientists and other observers laid on the ground for safety. At exactly 5:30 AM on Monday, the bomb was dropped over the Alamogordo desert. The bomb immediately disintegrated the tower to green dust. The bomb had formed a large fire cloud and created a large blast wave of heat and radiation. By mistake, during the army’s survey, some houses had been missed and were affected by the blast wave. In a small ranch, the windows had gotten blown out and burned the fur off of their cattle.

Now that the test had proven successful, America had the power of the atomic bomb to be used if Japan would not surrender. First, they had to make a peace treaty. America and allied leaders met in Potsdam, Germany to discuss peace settlements. They wanted Japan to surrender unconditionally and wished to write a document including terms they wanted Japan to accept. This document was called the Potsdam Declaration and was issued on July 26, 1945. When presented to Japan, it was declined. It was now time for America to bomb Japan.

The final agreement to use the bomb on the city of Hiroshima was made on July 25. Colonel Paul Tibbets had carefully selected his bomber crews months prior to the final authorization. They had already been practicing, for months at this point, dropping bright orange, 5,000-pound dummy bombs, which the crew had nicknamed pumpkins. They had done this both to practice for the dropping of the real bomb and to get Japan used to flights of B-29s overhead.

Early on the morning of August 6, 1945, Colonel Paul Tibbets and his bomber crew took off from Tinian island. They headed to Hiroshima with Tibbets operating the B-29 plane, called the Enola Gay, containing the 9,700-pound bomb, nicknamed “Little Boy”. They removed the two green safing plugs, and replaced them with red arming plugs, making the uranium gun-type bomb active.

The Enola Gay made its destination over Hiroshima and was ready to drop “Little Boy”. The bomb, “Little Boy” was dropped at 8:15 AM, coincidentally over a military parade. The plane quickly dove out of the way and landed on a nearby Japanese island.

Almost instantly, a mushroom cloud formed over Hiroshima, killing thousands of people. The blastwave caused a huge explosion with a blinding light and high heat. It burnt patterns onto people’s skin from their clothes, instantly turned bodies to black char, turned birds to fireballs, knocked people off their feet, collapsed buildings, and shattered glass up to twelve miles away.

The blastwave also caused highly flammable items such as paper to catch on fire. These tiny fires appeared all around the city as they spread to other objects and caught larger things on fire. Soon all of the fires formed together and made one huge fireball that consumed 4.4 square miles of the city. The blastwave caused many leg fractures, which made it very difficult for people to escape the large fire.

The radiation also affected pregnant women. Most of the women who were pregnant reported that they had miscarriages within weeks of the bombing. Most of those who did not have miscarriages, had babies with birth defects at birth.

The radiation caused illness in those near the bomb. About a week or two after the bombing, nurses had discovered what were the first symptoms of these new radiation cancers. This caused just about as many deaths as the deaths from those who died in the fire cloud or from the blastwave. There were an estimated 100,000 deaths from effects from radiation including cancer and other illnesses. There were an estimated 200,000 deaths total, including deaths from the fire cloud, deaths from the blastwave, and deaths from radiation illnesses.

Later on the day of the bombing, at 11:00 AM (Washington D.C. time), Truman’s message played to the United States. It informed the citizens of a completely new type of bomb called an “atomic bomb” that was dropped on Hiroshima. Truman warned Japan if they didn’t surrender unconditionally that the United States military would drop another atomic bomb with a proportionately disastrous outcome.

Power in the unharmed areas was fixed the next day and minimal rail service the day after. The Japanese first discovered what had happened 16 hours after Truman’s message played in the United States. Workers from unharmed cities came in but relief was slow.

On August 9, 1945, B-29s were sprinkling leaflets all around Japan. They warned the citizens of Japan, “We are in possession of the most destructive explosive ever devised by man. A single one of our newly developed atomic bombs is actually the equivalent in explosive power to what 2,000 of our giant B-29s can carry on a single mission. This awful fact is one for you to ponder and we solemnly assure you it is grimly accurate. We have just begun to use this weapon against your homeland. If you still have any doubt, make inquiry as to what happened to Hiroshima when just one atomic bomb fell on that city.” (, pg 2) At this time, Tibbets’s crew was preparing for a second bomb drop.

Soon after, America represented the Potsdam Declaration to Japan. Japan rejected the document and secretly tried to find a way to surrender conditionally. They had negotiations with Russia, which America had found out by decoding secret messages going between the two countries. All that America’s leaders were waiting for was the weather to clear, and a second bomb was to be dropped on Japan. The final decision to bomb Japan for a second time was made on July 25, 1945.

The second bomb was ready in early August 1945, and was nicknamed “Fat Man”. America hoped this would lead to Japan’s unconditional surrender. Kokura was the prime target for this bomb due to its large military center.

Bockscar was the B-29 chosen for this bomb, and it had to be deprived of most of its armor due to “Fat Man’s” heavy weight. “Fat Man” weighed five tons, was five feet around, and eleven feet long. It was egg-shaped and painted a yellow color.

Bockscar waited in Tinian Island for two other planes that were supposed to show up. The first was the Great Artiste, a plane designated to evaluate the bomb’s power. The second was Big Stink, a camera plane. Big Stink never showed, so Bockscar and Great Artiste had to take off without it.

Great Artiste and Bockscar reached their destination over Kokura before they realized it was too cloudy, and were not able to see their target. Even to this day, no one can explain exactly where the clouds had come from. There are three common possible explanations for these clouds. The first explanation was a deliberate discharge of steam,
which was done any time there may have been an overflight of bomber planes. The second explanation was leftover dust from a previous American attack, only the day before in a nearby city. The third explanation was simply that the weather had changed.

The crew had to decide quickly what they were going to do. They only had 45 minutes of fuel left, and anti-aircraft were coming after them. They decided it was too risky to try to drop the bomb in these clouds, and tried to find another city. With the list given to them, they decided which city to head to. With only 45 minutes of fuel left, and Nagasaki being the closest city, they headed that direction.

They reached their destination and dropped the bomb over Nagasaki at 11:02 AM, August 9, 1945. The target of where they wanted the bomb to land was a military base. After the bomb had been dropped, it ended up being two miles northwest of this military base. The effects of this bomb were the same as those on Hiroshima, except less disastrous.

Years after the bombings, General Leslie Groves, the micro-managing head of the Manhattan project, confessed many unplanned things had happened during the second bomb. For one, he had never figured out when Nagasaki had been added to the draft list. Nagasaki had been on the initial list when they first started putting together potential targets, but it had been removed and replaced by superior targets when a shorter list had been put together. On the final draft, written on July 24, 1945, the document listed “Hiroshima, Kokura, and Niigata in the priority listed.” On the final document, someone had crossed out “in the priority listed” and scribbled in “and Nagasaki”. Even today it is still unclear who had done this.

After this bombing, Japan accepted the Potsdam Declaration on August 14, 1945. After this, the war between Japan and America concluded, and Japan dropped out of the war completely.

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Bombings of Hiroshima and Nagasaki. (2021, Apr 06). Retrieved from

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