Atomic Bomb on Japan

Background Information

The Allies won WWI and had taken the Polish Corridor from Germany (Beck 491). WWII started when Hitler wanted the Polish Corridor back in 1939 (Beck 491). The Allies declared war on Germany when Hitler annexed the western half of Poland, and WWII started (Beck 491). The Allies were not doing well, so President Roosevelt was concerned (Beck 496). He knew if the Allies fell, the U.S. would have to join the war (Beck 496). So, he aided the Allies by selling arms to them (Beck 496). Germany did not let the British carry American arms through the seas easily, and America wanted to support the Allies (Beck 496). So, defending the British, America helped them fight Germany overseas (Beck 496). America was not interested in officially entering the war, though. The reason they finally joined WWII was not because of Germany, but surprisingly, because of Japan (Beck 496). The Japanese attacked Pearl Harbor on December 7, 1941 for various reasons (Beck 497) which angered the U.S. causing them to enter the war on the same day (Beck 497).

About the Atomic Bombs and the Bombing on Japan

World War II was a total war, meaning the countries would do anything necessary to win the war, not taking civilians lives into much consideration (Decision to Use the Bomb). The Allies expected "unconditional surrender" from Japan and would accept no less (Grant 12). Japan's policy was "no surrender" (Grant 18). The first four months of fighting left the Allies almost hopeless because of Japan's continuous victories (Ziff 39), but the Allies began to victor in the Battle of the Coral Sea and the Battle of Midway (Beck 500) which gave them a boost of confidence and morale. General Douglas MacArthur came up with a solution for the great distances in the war in the Pacific which finally put the Allies on the offensive side of the war (Beck 500). He thought up "island hopping" which means the Allies would go from one island to another seizing Japanese strongholds, leading them closer to Japan (Beck 500). This tactic proved to be successful. The Allies won a hard earned victory in the Battle of Guadalcanal which stopped the Japanese from advancing anymore in the Pacific (Beck 511). On April, after some of the most brutal fighting in the whole war, the Allies got Okinawa which was only 350 miles from southern Japan (Beck 511). An invasion of Japan would end the war. However, an invasion would be problematic. Sitmson, the secretary of war in 1945, warned Truman by saying half a million lives from the Allies side would be lost if they invaded Japan (Grant 22).

Manhattan Project

There was an alternative to invasion. President Roosevelt first heard of "extremely powerful bombs of a new type" in October 1939 from Einstein (Grant23), which was before America joined the war. There was a great race amongst all nations involved in WWII (Grant 24) to get the ultimate weapon first, the atomic bomb, since this would give them power and they would win the war. It was crucial for Germany to not make an atomic bomb first so, Roosevelt set up the Uranium Committee to begin making a bomb in America, but it was not given the utmost importance (Grant 24). As soon as the U.S. joined the war though, the Manhattan Project began, and it worked hard and fast under the command of Leslie R. Groves and the lead nuclear physicist, Robert Oppenheimer to make the bomb (Grant 24). The first atom bomb was tested in Los Alamos, New Mexico and it was a success (Atomic Bomb).

The Decision to Drop the Bomb

The Japanese resisted surrender as much as possible. Americans were angry from the attack on Pearl Harbor, the cruel way they treated prisoners, and more. When The Allies issued the Potsdam Declaration, Japan completely ignored it. Truman decided to drop the bombs.

Dropping the Bombs

Two atom bombs were dropped on Japan that bought severe short and long term damage. The first was made of uranium and was nicknamed “Little Boy” (Grant 26). This one was dropped on Hiroshima . On August 6, 1945 an American B-29 plane named the Enola Gay flown by Colonel Tibbits was carrying “Little Boy” (Victory in Japan). The bomb exploded at 8:16 AM (Ziff 74). The second bomb was made of plutonium and nicknamed “Fat Man” and was dropped on Nagasaki only three days later on August 9th (Grant 42). The effect of this second bomb was not as devastating as the first, but it still was just the same affect on civilians lives (Grant 42). The bomb exploded at 11:02 AM in a valley between two hills (Grant 43).

The Importance of the Atomic Bombs For the Allied Victory in WWII

The major importance of the atom bombs was it ultimately ended WWII. Japan could not evade the inevitable and they surrendered on September 2, 1945 (Isserman 253). How the bomb affected Hiroshima shocked Japan. Their morale was lost. But militarists refused to back down and wanted to fight more (Decision to Use the Bomb). However, the bombing of Nagasaki only three days later made the government argue more than ever and could not decide what to do (Decision to Use the Bomb). The emperor was called upon for his opinion (Decision to Use the Bomb). He, other peacemakers, and all of Japan finally decided to agree to the Potsdam Declaration as long as the emperor can stay (Grant 44). In fact, the disaster the bombs caused helped the Japanese leaders who wanted peace to persuade and win the argument over whether or not to surrender against Japanese militarists "who wanted to fight on" (Grant 46). Since the Japanese were the last to surrender to the Allies, as soon as they did, WWII was history. On September 2, 1945, Japan officially surrendered by signing documents on the U.S. battleship, Missouri , docked in Tokyo bay (Isserman 203). In World War II, it is stated that "General Douglas MacArthur accepted this surrender on behalf of the Allies" by saying:

It is my earnest hope and indeed the hope of all mankind that from this solemn occasion a better world shall emerge out of the blood and carnage of the past- a world founded upon faith and understanding- a world dedicated to the dignity of man and the fulfillment of his cherished wish- for freedom, tolerance and justice (203).
World War II was finally over.

The Devastation of the Atomic Bombs On Japan

The bombing on Hiroshima and Nagasaki absolutely tore both cities apart. People near the explosion vaporized, hair and skin were burned off of people some distance away, some even went blind (Grant 6). Factories, buildings, housing, and vehicles were demolished (Grant 6). People spontaneously caught fire and when the jumped into the Ohta River to save themselves from the heat, they died (Grant 6). The explosion's effects did not end after the bombing. Long after the war ended, many others died from radiation sickness (Ziff 101). Apart from the physical effects on the people and city, Japan's economy was heavily affected (Beck 515). Just the direct war costs was $41.3 billion (Beck 515). People were also very psychologically affected. The atomic bombs were not easy to take in for Japan. They completely surprised and shocked the entire Japanese population as much as or more than Pearl Harbor affected Americans. It was not a good time to be in either bombed city.

Bombing of Hiroshima: Effects Table

Ground temperatures
7,000 degrees Fahrenheit
Hurricane force winds
980 mph
Energy released
20,000 tons of TNT
Buildings destroyed
62,000 buildings
Killed immediately
70,000 people
Dead by the end of 1945
140,000 people
Total deaths related to A-bomb
210,000 people

President Truman was responsible for the decision of dropping the atomic bomb on Japan.
President Truman was responsible for the decision of dropping the atomic bomb on Japan.

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The Atomic Bomb Dropped on Hiroshima

Two atom bombs were dropped on Japan that bought severe short and long term damage. The first was made of uranium and was nicknamed “Little Boy” (Grant 26). This one was dropped on Hiroshima . On August 6, 1945 an American B-29 plane named the Enola Gay flown by Colonel Tibbits was carrying “Little Boy” (Victory in Japan). The bomb exploded at 8:16 AM (Ziff 74).
Atomic Explosion on Hiroshima on August 6, 1945
Atomic Explosion on Hiroshima on August 6, 1945

The Atomic Bomb Dropped on Nagasaki
The second bomb was made of plutonium and nicknamed “Fat Man” and was dropped on Nagasaki only three days later on August 9th (Grant 42). The effect of this second bomb was not as devastating as the first, but it still was just the same affect on civilians lives (Grant 42). The bomb exploded at 11:02 AM in a valley between two hills (Grant 43).
After the Bombing
Many people tried to stay where they were and move on. Some lived in partially destroyed homes or apartments but some huddled in cellars or caves made from rubble. They had no water, electricity, and very little food. But a large number of people did not stay where they were. They left an went to other European countries so find their family and other places to live. (Beck 514-515).


Damages on buildings after the bomb. Everything is completely destroyed.
Damages on buildings after the bomb. Everything is completely destroyed.

A person severely injured and with skin completely burned off after the explosion of the bomb
A person severely injured and with skin completely burned off after the explosion of the bomb




Works Cited
"Atomic Bomb." Factmonster.com. Factmonster, 2000-2011. Web. 11 May 2011.

Beck Et Al , Roger. "Chapter 16 World War II ." Perspectives on the Past. 2005. Beck,Roger Et Al. Evanston , Il: McDougal Littell, 2005. Print.

"Decision to Use the Bomb." The Atomic Bomb n. pag. Web. 11 May 2011.

Grant, R. Hiroshima and Nagasaki . New York : Raintree Steck~Vaughn Publishers, 1998. 4-47. Print.

Isserman, Maurice. World War II. New York: Facts on File, 2003. 194-202. Print.

"Victory in Japan ." History.com. A&E Television Networks, 1996-2011. Web. 12 May 2011.

Ziff, John. The Bombing of HIroshima . Philadelphia : Chelsea House Publishes, 2001. 55. Print.