1. The Dropping of The Atomic Bomb at Hiroshima and Nagasaki
The atom bomb was no great decision. It was merely another powerful weapon in the arsenal of righteousness.
~ Harry S. Truman
We chose a dark background to represent the atom bomb to demonstrate a dark and somber mood. The background is a picture of the mushroom cloud after the atomic bomb was dropped in Nagasaki. The pictures on the left side show the actual atom bombs and the mushroom cloud after a detonation. The font we used is “1942 Report” which we believe looks like a typewriter font. The font also looks somewhat destroyed which coincides the destruction of the atomic bomb.
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Charles C. and Ben S. Horace Greeley HS Chappaqua, NY

2. Essential Question
What were Harry Truman’s motivations for using the Atomic Bomb against Japan in World War II?
The topics of Truman’s actions and decisions will be discussed later on. (What events caused Harry Truman to use the bomb?)
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3. Nuclear Programs: Germany
Germany started experimenting with Nuclear Fission in 1938.
German scientist Otto Hahn and Fritz Strassman bombarded Uranium with neutrons and discovered Barium atoms.
Conclusion: Nuclear fission releases a massive amount of energy
The German nuclear energy project was developed in WW II in Nazi Germany. By the beginning of WWII, the scientific community was well aware of early German leads in nuclear physics. The German nuclear energy project led to severe rivalry among nations. As a result, the British created TUBE ALLOYS, which eventually resulted in the Manhattan Project.

4. German experimental nuclear pile at Haigerloch
The project was not a success. However, the discovery of nuclear fission led Robert Frisch and Lise Meitner to give a rough description of the mechanisms of fission and its immense potential power. The German government never financed a program to develop weapons because they felt the weapons would not be ready for the war. Therefore, the German program was not as advanced in comparison to the Manhattan Project. The German nuclear energy project was a pioneer in nuclear fission, which would lead to mass competition in the future.
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5. Project Alsos
U.S. investigation in 1945 determined that the Germans have not created a sustained nuclear chain reaction.
By creating a chain reaction, the Germans could create a nuclear reactor for nuclear power or absolute destruction.
It is debated whether German scientists sabotaged their success of their nuclear program purposefully or whether their estimates were simply inaccurate and inadequate.
Project Alsos was a U.S. investigation in 1945, in which the U.S. concluded that the Germans did not create a nuclear reactor. After WW II, German scientists such as Otto Hahn, Erich Bagge, Walther Gerlach, etc were captured by the Allies and kept at Farm Hall, England. Under Operation Epsilon, the conversations of the scientists were recorded in order to gain German knowledge about nuclear weapons.
Operation Epsilon was not a success because the Allies gained very little from the scientists conversations. However, when Otto Hahn was told about the dropping of the atomic bombing in Japan, he turned suicidal.

6. No Bomb for the Germans
June 1942 – German atomic program slows down because Germany felt victory in WWII was imminent.
U.S. and Britain were not aware that the Germans decided not to build a bomb.
Japan also had an atomic program but was not successful.
If Germany and Japan had created an atomic bomb, it would be used against the Allies.
In 1942, Germany decided that the construction of an atomic bomb was too large an investment and the project would severely disrupt the economy. Another reason for Germany’s decision to abandon its nuclear program was because they already expected to win the war. The United States and Britain were unaware of Germany's decision and continued to assume that the Nazis would acquire the atomic bomb, possibly before the Allies did. This led Americans to adhere to their program and beat the Germans. The U.S. needed to construct its own program in order to keep up with the competition.

7. Failure of the German Nuclear Program
When Adolf Hitler was in power, Hitler encouraged many top scientists to leave Europe.
Heavy water was not easily accessible.
No known factories for the production of nuclear missiles.
Paris Treaties of 1955
There has been great debate on whether the Germans actually built a nuclear bomb or not. However, there is more evidence proving that even though German scientists discovered nuclear fission, a nuclear bomb was nowhere no completion. First of all, Hitler dispersed many top scientists, which could have aided in the nuclear effort. Second, heavy water, a main component to making a nuclear reactor, was accessible only in Vemork, Norway. When the Norsk Hydros plant in Norway was damaged, the German scientists no longer had access to the necessary component. Third, if the Germans were making a bomb, German production factories would be a primary target for the Allies. Lastly, in the Paris Treaties of 1955, Adenauer had a “non-nuclear pledge” in which chemical and biological weapons were forsworn .

8. Japanese Atomic Program
The Japanese atomic program was run by Empire of Japan in order to develop a “genshi bakudan” or atomic bomb.
This project started around the same time as the Manhattan Project.
Japan did not complete their atomic bomb by World War II.
The Japanese program was similar to the German program in the sense that neither created a successful atomic bomb. Most experts believe that the Japanese program was small, and did not refine enough uranium-235 nor breed enough plutonium needed for the bomb. The surrender of Japan on August 15, 1945 ceased atomic production .

9. Hideki Yukawa
Hideki Yukawa was a Japanese theoretical physicist who was the first Japanese man to win the Nobel Peace Prize.
In 1935 Yukawa published his theory of mesons, which explained the interaction between protons and neutrons.
His writing quickly became a major influence on research in elementary particles.
Yukawa (January 23, 1907-September 8, 1981) and his conclusion about the interaction of protons and neutrons were groundbreaking. This information became very useful for countries with nuclear programs. Yukawa predicted “K-capture” which is when a a low energy hydrogen electron is easily absorbed by the nucleus.
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10. Einstein’s Letter
In the course of the last four months it has been made probable - through the work of Joliot in France as well as Fermi and Szilard in America - that it may become possible to set up a nuclear chain reaction in a large mass of uranium, by which vast amounts of power and large quantities of new radium-like elements would be generated. Now it appears almost certain that this could be achieved in the immediate future.
This new phenomenon would also lead to the construction of bombs, and it is conceivable - though much less certain - that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory. However, such bombs might very well prove to be too heavy for transportation by air...
Yours very truly,
(Albert Einstein)
Einstein sent a letter to F.D.R. on August 1939 regarding the construction of an atomic bomb. The letter helped start the American atomic bomb project, but the United States did not immediately begin a crash program to build nuclear weapons. Leo Szilard was a Germany refugee physicist who discovered the nuclear chain reaction as a means of liberating atomic energy and creating an atomic bomb. Szilard worked for the Manhattan Project's Chicago laboratory. Einstein’s letter was taken seriously and America prepared itself for a top secret nuclear program.
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11. The Beginning of A Crash Program
American atomic bomb project in its early stages in 1941.
Independent research was done in Britain.
Vannevar Bush hears of German program.
October 9, 1941 U.S. starts significant research for the construction of an atomic bomb.
Even before Pearl Harbor (December 7, 1941), the American atomic bomb program began picking up speed, but was not yet a top concern. Research held in Britain concluded that construction of an atomic bomb was possible. The initiation of the American crash program began to become a top priority when Vannevar Bush, head of the American civilian scientific research for the American military, found that the Germans had their own nuclear program. On October 9, 1941, President Roosevelt approved intensified research resulting in a feasible atomic bomb.

12. The Manhattan Project
June 1942, atomic-bomb project was controlled by War Department's Army Corps of Engineers.
American and European physicists discovered that the fission of uranium could a powerful weapon.
Major General Leslie Groves named head of the project.
At the height of construction in mid 1944, the Project employed nearly 129,000 people. No other nation in the world had the massive industrial capacity to make this possible.
The Manhattan Project was a very top secret project to counter the German nuclear program. America felt threatened by the German program and therefore, we created our own nuclear program. Albert Einstein, a German American scientist, believed that the Germans would create an atomic bomb. However, the Germans created an atomic bomb. In June 1942, President Roosevelt transferred the atomic-bomb project to the War Department's Army Corps of Engineers. Groves' major task was to build the huge industrial facilities needed to separate the small amounts of uranium and plutonium needed for a bomb. The Manhattan Project was truly a confidential program. Even Harry Truman were not even aware of the program until he took office.

13. The Manhattan Project Cont.
To disguise this ultra-secret project, the Corps created a Manhattan Engineer District, with a headquarters initially based in New York City.
Most work done at Los Alamos, New Mexico
“Gadget” (Trinity) on July 16, 1945
Clearly, the Manhattan Project was initiated as a defense mechanism. With the fear of other countries, especially Germany, establishing nuclear programs, the United States needed to start a program to defend itself. If a program was not established, the United States would be in grave danger. The Manhattan Project was top-secret, Harry Truman was not aware of the program until early Most of the Manhattan Project was centered around Los Alamos, New Mexico, under the direction of American physicist J. Robert Oppenheimer, who designed and built the first atomic bombs. On July 16,1945, the first nuclear device known as the “Gadget” (Trinity) was detonated near Alamogordo, New Mexico

14. Robert J. Oppenheimer
When you see something that is technically sweet, you go ahead and do it and you argue about what to do about it only after you have had your technical success. That is the way it was with the atomic bomb.
The atomic bomb made the prospect of future war unendurable. It has led us up those last few steps to the mountain pass; and beyond there is a different country.
Robert J. Oppenheimer (April 33, 1904-February 19, 1967) was the director of the atomic bomb project in Los Alamos, New Mexico. His quote above. It shows irony and serves as a prelude to Harry Truman’s ultimate decision. He was known as the “father of the atomic bomb.” The picture of Oppenheimer gives the impression of “what have I done.” He seems bittersweet and at war with himself.
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15. Robert J. Oppenheimer cont.
Late in 1942, Gen. Groves chose physicist J. Robert Oppenheimer to head a new laboratory devoted to the designing atomic bombs.
Oppenheimer recommended a remote site in New Mexico for the new facility, where many famous scientists could work together in complete secrecy.
From a wealthy N.Y. Jewish family.
Ties with Communism.
By choosing a very remote area, such as Los Alamos, New Mexico, top scientists could work under isolated conditions. It is very important that the project remained secret so no confidential information could be leaked to the public. Oppenheimer was from a wealthy New York Jewish family and became a brilliant student of theoretical physics. The Nazi persecution of the Jews turned him into an activist but he held ties with Communists. Oppenheimer proved to be a great leader and scientific manager. After the war, he played an important role in advising the U.S. government about nuclear weapons.

16. Letter to Harry Truman April 24, 1945 Dear Mr. President,
I think it is very important that I should have a talk with you as soon as possible on a highly secret matter.
I mentioned it to you shortly after you took office but have not urged it since on account of the pressure you have been under. It, however, has such a bearing on our present foreign relations and has such an important effect upon all my thinking in this field that I think you ought to know about it without much further delay.
Faithfully yours, Henry Stimson Secretary of War
In this letter from Secretary of War Harry Stimson to President Harry Truman, Stimson hints at the top-secret atomic bomb. Stimson expresses urgency in his tone. The Manhattan Project is currently coming to an end, and the bomb is near its completion. Truman, as well as most of his administration were unaware of the full details of the Manhattan Project to ensure top security.

17. Los Alamos National Laboratory
Los Alamos National Laboratory is one of the two laboratories in the United States where classified work towards the design of nuclear weapons have been undertaken. The other location is Lawrence Livermore National Laboratory.
During the Manhattan Project, Los Alamos was home to thousands of employees.
The first nuclear test was located near Alamogordo, New Mexico, under code name “Trinity” on July 16, 1945.
Los Alamos National Laboratory was also known as Site Y; The nuclear weapons were designed here. Almost all the research and experimentation that went into building the atomic bomb took place at the Alamos National Laboratory. The Los Alamos staff made a crash effort to design two different kinds of bombs, one using uranium, the other plutonium. Hundreds of scientists spent countless hours working to fulfill the goal of creating the worlds first atomic fission weapon.

18. The Manhattan Project Success
Two atomic bombs were made, “Little Boy” and “Fat Man.”
Scientists at Los Alamos were not fully confident in the “Fat Man” bomb.
Bombs designed to create an accurate and symmetrical implosion.
After over three years of top secret work, The Manhattan Project produced two different types of atomic bombs. The "Little Boy“ was designed to trigger a nuclear explosion by firing one piece of uranium 235 into another. The "Fat Man" was far more complex. It contained a sphere of the metal plutonium 239, around which were arrayed blocks of high explosives. At Los Alamos, scientists were not fully confident in the “Fat Man” so they believed that it should be dropped first as a test of its destruction. Both bombs were designed to produce a accurate and symmetrical implosion, which would compress the plutonium sphere to a critical density and set off a nuclear chain reaction.

19. “Trinity” July 16, 1945
The “Trinity” test was the first successful test of a nuclear weapon. The bomb tested an implosion-design plutonium bomb. This type of bomb was used in Nagasaki. The explosion was the equivalent of 20 kilotons of TNT. The test signified the beginning of the “atomic age.”
Betting pools were set up among the observers of “Trinity” on the results of the test. Some predictions ranged from zero, a dud, to 18 kilotons of TNT to destruction of the state of New Mexico to the ignition of the atmosphere and incineration of the planet.
This first nuclear explosion cast an ominous shadow over many, especially Oppenheimer. Robert Oppenheimer later said he thought of the lines from the Hindu scripture, the Bhagavad-Gita, "I am become Death, Destroyer of Worlds."
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20. Fission Bomb
The names of the two atomic bombs were “The Fat Man” and “The Little Boy.” The Little Boy bomb was a gun-type fission bomb (shown above). Gun-type bombs generate a nuclear explosion by firing one piece of fissile material into another of the same type. In this case, the material is uranium. The bomb is gun-like in that a small wedge of uranium is fired at a larger, target piece. Upon impact, the two pieces fuse together briefly, forming what is called a supercritical mass (a mass slightly greater than what is necessary to sustain a chain reaction). The rapid release of massive amounts of energy in a limited volume creates the explosion. In the Little Boy bomb, a mass of uranium about the size of a baseball produced an explosion as powerful as 20 kilotons of TNT. (Microsoft Encarta Encyclopedia.)
Picture from – “Fission Bomb” Microsoft Encarta Encyclopedia

21. Fat Man and Little Boy “Fat Man” “Little Boy”
The picture model shown above shows the type of bombs that were dropped in Japan. In Hiroshima, the Fat Man was a gun-type assembly method bomb. In Nagasaki, the Little Boy was an implosion assembly method type bomb. Japan estimates a death toll of of 240,000. Once again, the immense radiation is detrimental to health, and can create problems such as thyroid cancer. Those that survived the bomb are called hibakusha (exposed to the bomb). Today, there are over 266,000 hibakusha in Japan.
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“Little Boy”

22. New Weapons in World War II
During the last stages of the war, two new weapons were introduced: the long-range rocket and the atomic bomb.
Throughout the war, most weapons were an improved version of the weapons used in World War I.
Atomic bomb = absolute destruction.
Towards the end of the war, the American government had successfully created an atomic bomb. This atomic bomb had the potential to create absolute destruction. America beat Germany in creating the bomb and had the entire world watching. The use of the bomb could sing handedly end World War II, however, the dropping of the bomb would have adverse effects on those it was used against and those who used it.

23. Russian Influences on Development of the Atomic Bomb
The US carefully considered Russia in the development of the Atomic Bomb.
General Groves viewed the Soviet Union as one of America’s worst enemies.
Truman’s advisors convinced him that if the Atom bomb was used, it would keep the US’s enemy Russia at bay.
Postwar use of the bomb as a bargaining chip for territory was highly valued.
Postwar uses for the Atomic bomb were often thought about throughout the development of the Manhattan Project. High ranking generals and advisors viewed the Soviet Union as the exact opposite of the United States. Truman’s lack of foreign policy made it easy for outside influences to dictate his final decisions. The US believed that as long as it was the only nation with the atom bomb, it could influence every country in the world. Therefore, the decision to drop the atomic bomb was made to show Russia and the world that the US is in control.

24. A Chance for peace?
One week before Roosevelt's death, Japanese Prime Minister Kuniaki Koiso and his cabinet resigns.
Second resignation of Prime Minister in two years.
Japan believed “unconditional surrender” was not tolerable.
Kantaro Suzuki was named new Prime Minister.
Japanese Prime Minister Kuniaki Koiso and his Cabinet resigned because of the increasingly disastrous course of the. The peace faction in the military-dominated Japanese government began to realize to negotiate an end to the war. However, the Japanese viewed the Allies “unconditional surrender” to be non-negotiable. Emperor Hirohito approved the New Prime Minister Kantaro Suzuki could not achieve a unanimous decision because of the tensions between the peace faction and the militarists. Here, Japan had a chance to end the war, but political factions prevented peace.

25. Battle of Okinawa Known as “Typhoon of Steel”
Largest amphibious assault in Pacific of the War.
Operation Downfall – invasion of main islands in Japan
48,000 Americans died. 150,000 Japanese civilians died.
Japanese propaganda viewed Americans as “barbarians.” This gave the Japanese the mindset of never surrendering to an American.
The Battle of Okinawa (April 1, 1945-June 21, 1945) resulted in massive causalities and was no doubt the bloodiest battle of the Pacific Ocean. “Typhoon Steel” refers to the immense amount of gun fire. About 120,000 Japanese died. More civilians were killed than in the initial atomic bomb blast at Nagasaki and Hiroshima. Operation Downfall never occurred because the atom bombs were dropped in Hiroshima and Nagasaki. The Japanese portrayed Americans as barbarians in order to gain more support. Some civilians killed their families instead of surrendering. Also, the Japanese soldiers truly fought to the last man.
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26. Uses for the Bomb Against Germany or Japan
General Groves believed it could end World War II.
$2 billion used to build the bomb. Not using it would be a waste.
'If this weapon fizzles, each of you can look forward to a lifetime of testifying before congressional investigating committees." Gen. Groves to his staff, December 24, 1944
It was believed that he atomic bomb would be used against either Germany or Japan. Groves believed that the bomb could solely end the war. He also believed that the $2 billion investment for building the bomb could be justified by using the bomb. Secretary of War Harry Stimson said, "At no time, from 1941 to 1945 did I ever hear it suggested by the President, or any other responsible member of the government, that atomic energy should not be used in the war.“ Clearly, the atomic bomb was definitely going to be used. General Groves quote states that if the atomic bomb does not work, then his staff will face a life of questioning. \ However, he was absolutely in favor of using the deadly weapon.

27. Debate over the Bomb: American Support
Americans were suffering many casualties and the Japanese were showing no signs of possible negotiation.
A cease fire was non-negotiable.
If the United States dropped the atomic bomb, surrender and peace would probably occur.
By 1945, the Japanese and Americans inflicted a huge amount of causalities, especially at the battle of Okinawa. When Franklin Delano Roosevelt was still president in 1945, the Japanese showed no sign for peace. The Japanese repeatedly denied talks for peace and peace talks were unsuccessful. The never ending war gave rise to the potential use of the atomic bomb.

28. Potsdam Declaration July 26, 1945
Key Points:
1. We-the President of the United States, the President of the National Government of the Republic of China, and the Prime Minister of Great Britain, representing the hundreds of millions of our countrymen, have conferred and agree that Japan shall be given an opportunity to end this war.
13. We call upon the government of Japan to proclaim now the unconditional surrender of all Japanese armed forces, and to provide proper and adequate assurances of their good faith in such action. The alternative for Japan is prompt and utter destruction.
The Potsdam Declaration took place on July 26, Don’t be confused with the Potsdam Agreement, because that was something very different. The Potsdam Declaration was made by Harry S. Truman, Winston Churchill, and Chiang Kai-Shek and it basically outlined surrender terms for Japan. The first point above refers to Japan’s chance to end the war. The last point gives Japan one last chance to surrender or face “prompt and utter destruction.” (atomic bomb)
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29. Potsdam Declaration Cont.
Japan would be occupied until the declaration was signed.
The Japanese army would be allowed to return home.
Once the declaration was met, allied troops would be withdrawn.
“Japan shall be permitted to maintain such industries as will sustain her economy and permit the exaction of just reparations in kind, but not those which would enable her to re-arm for war. To this end, access to, as distinguished from control of, raw materials shall be permitted. Eventual Japanese participation in world trade relations shall be permitted. “
The Japanese were given very negotiable terms but failed to sign the declaration at first. Other aspects of the Potsdam Declaration included an end to militarism and under the Cairo Declaration, Japanese sovereignty would be limited to the islands of Honshu, Hokkaido, Kyushu, Shikoku and such minor islands as the Allies determined. Clearly the terms were lenient, especially the fact that Japan would be able to participate in world trade and rebuild their industrial economy. Unfortunately, Japan did not agree to the Potsdam Declaration until after atomic bombs were dropped.
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30. Japan’s Response to the Potsdam Declaration
Japan’s response was ambiguous.
Before Japan could agree to any surrender, the top military officials had to figure out a way to satisfy many different groups inside Japan.
Japanese official Suzuki used the word mokusatsu which had a few different English translations.
The US and the US newspapers interpreted the word to mean “reject” when in fact it could have meant something different.
The apparent rejection of the Declaration definitely sped up the process of using the atomic bombs.
To this day, it is not known what the Japanese official Suzuki meant by his statement. Japan’s rejection of the Potsdam Declaration gave Truman further motives to end the war as soon as possible. Therefore, the atom bomb seemed a compelling way to end the war immediately. Also, the US deciphered secret Japanese cables that clearly stated that Japan had no intention to surrender. A decoded cable from Japanese militarists to Japan’s ambassador in Moscow read, “We cannot consent to unconditional surrender under any circumstances. Even if the war drags on, so long as the enemy demands unconditional surrender we will fight as one man against the enemy in accordance with the Emperor’s command. (Signal 7)”

31. Unconditional Surrender
Established at the Casablanca Conference early 1943.
Popular because war aims were clear.
Gained Soviet and American support.
Prevents country from resurging to power (Germany).
Under Roosevelt in 1943 at the Casablanca Conference, Unconditional surrender was first proposed. This was popular because it was used to justify the war and make aims clear. This reassurance is important because the people should be properly informed. Unconditional surrender was important between the Western Powers and Soviet Union because it reassured Stalin. At first Stalin believed that the U.S. and Britain would side with the Nazis. Unconditional surrender was also a popular in the U.S. because the people did not want to experience what happened with the Treaty of Versailles in WWI. In WWI, unconditional surrender was not a policy and this allowed Germany to gain power and become a threat once again. If Japan agreed to unconditional surrender, the Allies were guaranteed and absolute victory.

32. Japanese View of Unconditional Surrender
Emperor Hirohito was totally against unconditional surrender.
Americans viewed Hirohito as a symbol of military aggression
Unconditional surrender  destruction of “divine” monarchy.
  One reason why unconditional surrender was unsuccessful in negotiation was because of the Emperor Hirohito’s traditional views. He, like many of his cabinet, believed that by accepting to the Allies terms, the Japanese political system and “divine” monarchy would be destroyed. Americans hated Hirohito and many wanted him to be executed or imprisoned. Undersecretary of State Joseph Grew believed that Hirohito was "the sole stabilizing force" capable of making the Japanese armed forces accept a surrender order.
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33. Emperor Hirohito
The atomic bomb convinced the Emperor to break the deadlock of Japan’s generals and accept the Potsdam Declaration
He gave three reasons, "a collapse of domestic morale” and two military concerns: “inadequate preparation to resist the invasion and the vast destructiveness of the atomic bomb and the air attacks” (Frank, 345).
The atomic bomb was given as the main reason for the surrender of Japan
The atomic bomb allowed Japans military officials to surrender and still keep their honor. “If military leaders could convince themselves that they were defeated by the power of science but not by lack of spiritual power or strategic errors, they could save face to some extent” (Frank, 347). Therefore Japanese leaders could believe that they were beat by the element of science.

34. Japan Will Fight Until the End
Imperial Conference in Tokyo – June 8th 1945.
“Fundamental Policy”
Japan is willing to fight to the bitter end as an underdog.
Surrender is not an option for Japan.
On June 8th, 1945 the Japanese held an Imperial Conference in Tokyo. In this meeting, top Japanese officials decided that their soldiers would “fight to the death.” The "Fundamental Policy" of Suzuki's government was to fight on, and to choose "honorable death of the hundred million" over surrender. For 2,000 years Japan had never been defeated. There was no word for "surrender" in the Japanese dictionary. Therefore, losing was not an option.
Japan did not believe it could defeat the United States, it did intend to negotiate an end to the war on favorable terms. Japan attacked Pearl Harbor on 12/7/1941 hoping it could delay American intervention, gaining time to solidify its Asian empire. Japan planned to fight a decisive battle that would bloody American forces, forcing the U.S. to negotiate a peace and leave Japan as it was; the emperor and the military government, in power.

35. Roosevelt’s Influences on Truman
Even though Truman and Roosevelt did not get along, Roosevelt’s legacy remained in power.
Roosevelt’s former advisors found it easy to mold the new president Truman’s foreign policy and his feelings toward the Soviet Union.
Kissinger said, “Soviet policies were explained to Truman in inherent bad faith model.”
These heavy influences made the decision to drop the atom bomb very optimal.
Roosevelt did not like the Soviet Union. Even though the US was its ally during World War 2, Roosevelt never fully trusted Stalin. He thought that the Soviet Union in the worst possible light. Roosevelt’s beliefs were carried on by his advisors and generals. When Roosevelt died, vice president Truman’s lack of experience with foreign policy resulted in the advisors and generals influencing his feelings towards Russia. The generals and advisors backed by Roosevelt’s beliefs influenced Truman’s decision to drop the atomic bomb on Japan.

36. Truman’s Motivations
It cost the US $20 billion (in today’s dollars) to build the atomic bomb.
The use of the atomic bombs in ending World War 2 prevented endless investigations of the Truman administration.
To put in perspective how much building the atomic bomb cost to make, the cost of all bombs, grenades and mines throughout World War 2 was $31.5 billion (in today’s dollars) and the cost of all the small arms materials used in the entire war was $24 billion (in today’s dollars). Therefore making the atomic bomb was extremely expensive and the US wanted to use it. After Germany surrendered to the Allied forces, all work on the atomic bomb program rapidly increased. The head of the Manhattan Project Dr. Oppenheimer said, “I don’t think there was any time where we worked harder at the speed-up than in the period after the German surrender and the actual use of the bomb.” It could be speculated that the tremendous cost for the bomb could have been a major reason for its use.

37. Truman’s Motivations Cont.
Many historians believe that a main reason for the use of the bomb was retaliation for the surprise and brutal attack on Pearl Harbor.
After the bomb was dropped on Hiroshima, Truman said “This is the greatest thing in history.” and “Nobody is more disturbed over the use of atomic bombs than I am but I was greatly disturbed over the unwarranted attack by the Japanese on Pearl Harbor and their murder of our prisoners of war.
Thousands of POW”S were mistreated
Even though it is impossible to know what Truman was thinking, it can be concluded that retaliation was a main cause in the dropping of the atomic bombs. The way Truman described the greatness of the weapon shows he was happy with its results. He said, “The only language they seem to understand is the one we have been using to bombard them. When you have to deal with a beast you have to treat him as a beast.” Truman was disgusted with the Pearl Harbor massacre and how American POW’s were treated throughout the war. Truman flexed the American muscle by using the bombs.

38. Saving Lives by Using the Bomb
Non-combatants were dying throughout Asia at the rate of 200,000 per month.
The complete naval blockade of Japan would have resulted in hundreds of thousands of deaths due to malnutrition, dehydration, and famine.
The atomic bomb saved thousands of American soldier’s lives
Hundreds of thousands of soldiers and civilians alike were dying every month throughout the Japanese Empire. Most Japanese soldiers only knew the Samurai style of fighting which consisted of fighting to the last man. This mentality would have yielded ten times the amount of casualties than the dropping of the atom bombs. Operation Starvation was the complete blockade of Japan, which completely cut off its imports.

39. Invading Japan?
If America did invade Japan, many Americans would have died.
Secretary of State James Byrnes claimed 500,000.
Total combat deaths after four years of war – 292,000.
It was believed that if the U.S. invaded Japan, many American lives would have been lost. Secretary of State James Byrnes claimed that the atomic bomb saved about 500,000 deaths. The U.S. military planners predicted that 20,000 – 110,000 combat deaths since November 1945 thus far. However the estimates for how many Americans would have died, will never be known. We do knot know how strong the Japanese resistance would be. Some military advisors believed that the American death toll would reach 1 million.
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40. Japan: A Constitutional Monarchy
Japan’s Constitutional Monarchy created many problems for the possibility of peace.
Surrender possible only with unanimous support.
Cabinet was dominated by militarists from Army and Navy.
Political stalemate.
Japan’s Constitutional Monarchy created many problems for negotiation because the only way an agreement would be met was through a unanimous decision. The Japanese cabinet was filled by militarists from the Japanese Imperial Army and Japanese Imperial Navy. These militarists were totally against any means of negotiation with the United States. The political stalemate did not help negotiations. Militarists were determined to continue fighting.. Some Japanese believed that the war could still be won by inflicting mass causalities on Allied Forces. Japanese soldiers will not surrender.

41. The Beginning of the End of Imperial Japan
By 1945, a Japanese victory would not be possible.
Use of kamikaze (divine wind) attacks damaged about 50 U.S. ships and sunk 17 during January 4 –
Many Japanese soldiers jumped off cliffs instead of surrendering to U.S. soldiers.
1945, U.S. Marines capture the island of Iwo Jima. About 6,800 U.S. causalities.
The next attack was scheduled for Kyushu in November 1945.
It was known that Japan had no way of winning at this point. The Japanese navy would not be able to come out in force again. The suicide air attacks known as kamikaze were used towards the end of WWII for Luzon in the Philippines. Finally, after a month long battle at Iwo Jima, a battle that inflicted great causalities, Iwo Jima was under American control. However, the strong morale and dignity of the Japanese soldiers at Iwo Jima reminded American soldiers that there would not be any easy victories.

42. Japanese Support
Some Japanese historians supported the dropping of the atomic bombs.
Salvation in the atomic bombing.
Koichi Kido – “We of the peace party were assisted by the atomic bomb in our endeavor to end the war.”
Hisatsune Sakomizu – “Golden opportunity given by heaven to end the war.”
It is very interesting that a Japanese citizen would be in support of the atomic bombings. Some Japanese historians believed that the atomic bomb ended the war and actually brought peace. Koichi Kido was one of Emperor Hirohito’s closest advisors and believed the bomb ended the war. Hisatsune Sakomizu agrees. Many historians believe the sole influence to peace was the atomic bomb. The peace faction of Emperor Hirohito’s cabinet supported the bomb.

43. Japan and the Soviet Union
There was a slight chance that peace could come through Moscow.
Japan desperately sought help from Stalin to fight defeat.
Japan wanted a conditional surrender with Allies.
Fall of 1944, Japan grew desperate for victory and sought for help from the Soviet Union, even though they were on the opposing side. After the Suzuki cabinet was appointed in April 1945, these initiatives were renewed. Japan wanted to negotiate a conditional surrender with the Allies. But they had to conceal this intention from the militarists who vowed to fight on until the Allies gave Japan more concession. This created an unsuccessful Moscow Initiative. The Moscow Initiative remained weak and nothing was really done.

44. U.S. and the Soviet Union
Soviet Union played a large role in the use of the atomic bomb.
Growing tensions between U.S. and Soviet Union –- puppet governments in Eastern Europe.
Stalin started a Soviet atomic bomb project in 1942.
Soviets helped defeat Germany, but Stalin was not popular with the Allies.
The Soviet Union played a large role in America’s use of the atomic bomb because of rising tensions between American and the Soviet Union. American was not fond of the puppet governments the Soviets established in Eastern Europe after the German defeat. There was also the question of when the Soviets should enter the Pacific war. U.S. military wanted the Soviets to enter the Pacific War before the U.S. invaded Japan, but Truman’s civilian advisers questioned its desirability. Joseph V. Stalin was another problem for the U.S. and Allies. Nobody supported his purges and absolute control. Also Stalin authorized a Soviet atomic bomb project in 1942, and this scared America.
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45. The Soviet Union in the Pacific War
As Germany weakened near defeat, U.S. wanted the Soviet Union to enter the Pacific War.
Yalta Conference – Feb. 1945, Stalin promises to enter Pacific War 2-3 months after Germany surrenders.
U.S. leaders start to have second thoughts on the Soviet Union’s entrance into the Pacific War.
The Nazi’s were nearing defeat and the U.S. wanted the Soviets to attack and pin down the huge Japanese Army in China. By attacking the Japanese Army in China, these Japanese troops would not be able to lend defense at home. Soon, the Yalta Conference took place on February Stalin promised to enter the Pacific war two to three months after Germany's surrender. However, American leaders started to double think the Soviets entrance into the Pacific. The U.S. Navy's blockade of Japan was nearly complete by April and making troop transfers from China would complicate things. Also, advisors to Truman began to think of after the war, and how the Soviets could influence a Communist Asia. It was believed that Stalin wanted Korea and China to become Communist after the war.

46. “Magic” & “Ultra“ “Magic” – U.S. discovers Japan wants Soviet help.
Unconditional surrender was not possible.
“Ultra” – Japan willing to fight until the end.
Further limited hope of negotiation with the Japanese.
In 1940, American intelligence were able to decipher messages between Tokyo and the Japanese Embassy in Moscow in operation “Magic.” U.S. Intelligence found that Japan sought the Soviet Union to help end the war without unconditional surrender. Japan wanted significant Allied concessions in order to end the war. In the summer of 1945, operation “Ultra” discovered that the Japanese were rapidly building its forces in southern Japan. “Ultra” and “Magic” hindered any chance for negotiation and even provoked American support for the war.

47. Interim Committee
The Interim Committee on post-war atomic policy discussed dropping the bomb on Japan without any formal warning.
May 31, 1945 meeting was held with Stimson (Sec. of War), James Byrnes (Sec. of state), and scientific advisers held by Dr. Robert Oppenheimer.
Committee decided not to formally warn Japan for the Hiroshima dropping.
U.S. needed to shock Japanese to surrender, so a warning was out of question.
The Interim Committee on post-war atomic policy had a moral question of warning Japan of the atomic bomb. At this point, Japan as well as most people in the world, did not know America possessed such a powerful weapon. The Committee decided that Japan should not be warned for two reasons. The first reason was that if warned, Japan may try to shoot down the bombers. Secondly, Japan may move POW’s into the target area. Therefore, Japan could not be warned. Also, the bomb dropped at Hiroshima was only a test, and after it was dropped, many scientists discovered that they underestimated the power of the nuclear weapon. Ultimately, the only way to really shock the Japanese would be through surprise.

48. Opposition to the Interim Committee
Leo Szilard and other Manhattan Project scientists believed Japan should be warned.
Without a formal warning would be immoral in the eyes of the world.
Also, scientists believed U.S. should tell Soviets before using the war  postwar arms race.
Chicago group – petitioned to President Truman.
Many scientists especially Leo Szilard and Oppenheimer believed that it would be immoral not to warn Japan of the atomic bomb. By not warning Japan, many most civilian causalities would occur, and make the U.S. look bad in the eyes of the rest of the world. Also, these Manhattan Project scientists believed that the Soviets should be notified of the atomic bomb in order to avoid a postwar nuclear arms race (in fact a nuclear arms race did occurs after the war). The Chicago group, sent petitions to President Truman, and approached Truman's adviser but Truman did not receive the petition until after the bombs were dropped.

49. Possible Target Locations
The target committee at Los Alamos from May 10 – 11, 1945, recommended Kyoto, Hiroshima, Yokohama, and arsenal at Kokura as possible targets.
The psychological effects on the Japanese citizens were important to the committee members.
The target location for the detonation of the bomb should be spectacular for international recognition.
Kyoto, Hiroshima, Kokura, and Niigata.
The committee rejected the use of the atomic bomb against a military objective due to the chance of missing a smaller target not surrounded by a large urban area. The psychological effects of the Japanese citizens were important to the committee because the United States wanted show its ultimate power by making a statement. Also, the Americans wanted to shock the Japanese into unconditional surrender. The target committee wanted an accurate drop so it insisted the dropping to occur on a clear day. Another aspect that lead to target choice was that the city must be undamaged by conventional bombing and had geographical layouts that would maximize damage from the bomb's blast wave. By the end of May 1945, the Committee selected, in order of priority, Kyoto, Hiroshima, Kokura and Niigata.

50. Truman’s True Beliefs
“We have discovered the most terrible bomb in the history of the world. It may be the fire destruction prophesied in the Euphrates Valley Era, after Noah and his fabulous Ark.”
“I have told the Sec. of War, Mr. Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children.”
“He and I are in accord. The target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives.”
Recovered from President Harry S. Truman’s private diary. It explicitly shows that he was against the use of atomic weapons for the destruction of Japanese civilians. However, he believed he made the right decision in using the bomb against Japan because ultimately he saved American lives. He very well knew the massive power of the bomb and was grateful that the US discovered it before Hitler or Stalin. From Truman’s July 25, 1945 diary entry.

51. Ulterior Motives for Atomic Bombs?
Some historians believed that the atomic bombs were used to scare and impress the Soviet Union, rather than Japan. And the US President who took the decision, Harry Truman, was culpable, they add.
Peter Kuznick, director of the Nuclear Studies Institute at American University states "He (Truman) knew he was beginning the process of annihilation of the species." "It was not just a war crime; it was a crime against humanity."
Kuznick claims that Truman's main motive was to limit Soviet expansion in Asia. Kuznick believes that Japan surrendered because the Soviet Union began an invasion a few days after the Hiroshima bombing, not because of the atomic bombs themselves, he says.
According to an account by Walter Brown, assistant to then-US secretary of state James Byrnes, Truman agreed at a meeting three days before the bomb was dropped on Hiroshima that Japan was "looking for peace".
Truman was told by his army generals, Douglas Macarthur and Dwight Eisenhower, and his naval chief of staff, William Leahy, told Truman that their was no military need to use the bomb. However, Kuznick’s arguments, however, were dismissed by Lawrence Freedman, a war expert from King's College London, UK. Freedman believes Truman’s decision to bomb Hiroshima was "understandable in the circumstances".
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52. Official Order To Drop Bomb
Stimson (Sec. of War) and Byrnes (Sec. of State) advised Truman to use the bomb. Spring and summer of 1945, Truman approves decision.
Decision was “noninterference.”
Lt. Gen. Carl Spaatz requested a written order.
Official order was issued on July 25th.
During the Spring and summer of 1945, President Truman approved the proposals to use the atomic bomb, presented by Stimson and Byrnes. Truman's decision "was one of noninterference.” This meant that the decision not to upset existing plans. Lt. Gen. Carl Spaatz, commander of the newly created U.S. Army Strategic Air Forces in the Pacific, requested a written order authorizing the use of the bomb. Thomas Handy, the Acting Army Chief of Staff in Washington, issued the order to Spaatz on July 25. President Truman could have reversed the order if Japan accepted the Potsdam Declaration.

53. Success
At 2 PM, just a few hours after the bomb was dropped on Hiroshima, General Leslie Groves called Dr. Robert Oppenheimer to tell him of the weapons mass success
Groves said “Apparently it went with a tremendous bang.”
Right after the tremendous success with the Hiroshima bombing, “Every effort is being devoted to their next objective” (Nagasaki three days later)
After Nagasaki it was mentioned that there will be a following objective implying that there could be a third bombing
The telephone conversation between Groves and Oppenheimer was very calm. Oppenheimer did not get excited when he learned that the project he and his colleagues had been working on for years was a success. Groves wasn’t happy that the mission was tactically perfect. They knew that all the hard work they put into creating and delivering the atom bomb resulted in tens of thousands of dead Japanese civilians.

54. The Atomic Bomb at Hiroshima
The audio above was a statement made by Harry S. Truman’s announcing the atomic bombing at Hiroshima on August 6, The audio was recorded via voice recorder from the “American Presidency Project” website because the website does not offer a direct download due to copyright issues. The picture above is of stunning mushroom cloud. Truman’s speech is confidence and assures an American victory. He mentions beating the Germans and pride in the U.S. for having the first atomic weapon. He also states some of his motivations for bombing Japan.
Audio clip adapted from -
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55. Hiroshima During World War II
Hiroshima, Japan had reached a population of over 381,000.
Due to evacuations, the city population dropped to 255,000 at the time of the attack.
The city’s building construction consisted of several reinforced concrete buildings and lighter structures such as small wooden workshops and houses.
Hiroshima consisted of many flimsy, wooden workshops and houses. Because of this, the city was vulnerable to immense fire damage. There were a few industrial plants located near the city. The fact that the city was built with relatively weak materials, the destruction of the atomic bomb was greater than expected.

56. The Enola Gay
On August 6, 1945, the B-29 Enola Gay, under colonel Paul Tibbits left Tinian airbase in the West Pacific.
The six hour flight went exactly as expected.
The bomb was armed midway and clear weather permitted for accuracy.
The Enola Gay dropped “The Little Boy” bomb over Hiroshima, Japan. Its crew trained at Wendover Army Air Field in Wendover, UT. as part of Project Alberta during the Manhattan project. The Hiroshima mission has been described as “tactically flawless”, and the crew returned safely to its base on Tinian to great celebration.
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57. Hiroshima Before The Atomic Bomb
The picture above is a model of Hiroshima pre-atomic bomb. Before the bombing, Hiroshima was a city of industrial and military significance. There were even some military camps located nearby. It was one of the few cities in Japan, nearly untouched by American bombing. Hiroshima was picked as a target location because there was a large population, no POW camps, and the hills nearby would be “spectacular” when bombed.
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58. Hiroshima After The Atomic Bomb
The model above shows the great destruction at Hiroshima. The entire city was decimated within seconds. It is estimated that 70,000 – 90,000 instantly perished. However, there are also unaccounted deaths due to the massive radiation from the bomb. About 90 percent of the buildings in the city were damaged or completely destroyed.
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59. The Mushroom Cloud
8:15 AM, “The Little Boy” was dropped over the center of Hiroshima
It exploded about 2,000 ft. above the city and had a blast the equivalent to 13 kilotons of TNT.
Due to radiation, approximately 152,437 additional people have died.
During the bombing, 70,000 – 90,000 instantly died. However, over time, the deleterious effects of radiation have taken over 150,000 lives. The radiation caused massive health damage to the inhabitants as well as future generations.
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60. Nagasaki During World War II
Nagasaki was one of the largest seaports in southern Japan.
The city was important during the war because of great industrial activity.
Most residences and industrial buildings were made of wood.
Since the city had been permitted to grow without any strict zoning laws, most buildings and residences were constructed closely to each other.
In a sense, Nagasaki was similar to Hiroshima in an industrial aspect. Nagasaki was an important city, not only for its large seaport, but for its industrial activity during wartime. Nagasaki was very active with producing ships, military equipment, and other war time goods. Also in comparison to Hiroshima, the wood construction of houses and buildings made a nuclear attack even more devastating.

61. Formal Warning to Japan
On August 10, 1945 thousands of leaflets were dropped over the city of Nagasaki
The leaflets called for a petition to the Emperor of Japan to stop the war and agree to thirteen consequences of an honorable surrender.
Now that the first atomic bomb was dropped on Hiroshima, top U.S. leaders felt that Japan deserved a warning before the second bomb was dropped. Thousands of leaflets were dropped on every major city in Japan. They used Hiroshima as an example of the destructive power of the US’s new weapon. America urged that Japan “accept the consequences and begin the work of building a new, better and peace-loving country.” Every leaflet concluded by saying in big bold letters, EVACUATE YOUR CITIES. These leaflets were dropped soon after the atomic bomb was dropped on Hiroshima (August 6, 1945).
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Sample Leaflet

62. Bockscar Sometimes called Bock’s car.
B-29 bomber Superfortress, flown by Major Charles W. Sweeney dropped the “Fat Man” on August 9, 1945.
The Bockscar did didn't have enough fuel to return to Tinian or Iwo Jima, so Major Sweeney flew the aircraft to Okinawa
for an emergency landing with practically dry fuel tanks.
When the “Fat Man” was dropped on Nagasaki, it is believed that a mushroom cloud of over 60,000 arose. Almost instantly, 40,000 of Nagasaki’s 240,000 residents died. Over 25,000 – 60,000 were severely injured. It is believed that died in the following months due to immense radiation.
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63. The Bombing: Nagasaki Before After
In the before and after pictures above, clearly the immediate effects of the bombing are disastrous. On August 1, 1945, high-explosive bombs were dropped on the city. After this bombing, school children were evacuated to rural areas. Five days later, August 6, 1945, Nagasaki experienced its first large scale-bombing. A little north of Nagasaki was a camp holding British POW’s. The atomic bomb saved their lives because they were working underground in the coal mines while the atomic bombs were dropped.
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Before
After

64. Japanese Realization
Tokyo control operator of JBC noticed Hiroshima station went off air.
Complete silence when military bases called Army Control Station.
White House public announcement was Tokyo’s first knowledge of the attack.
Japan did not immediately surrender after the bombings. Emperor Hirohito was forced to agree to the Potsdam Declaration.
At first, the Japanese government was not aware of the attacks. In Tokyo, the control operator of the Japanese Broadcasting Corporation (JBC) did not receive a response from the Hiroshima station. Japanese military bases tried to contact the Army Control Station in Hiroshima and did not receive a response either. A young officer of the Japanese General staff flew over Hiroshima and witnessed the great destruction. Tokyo first gained information on the disaster from Harry Truman at the White House public announcement, 16 hours after the attack.

65. Japanese Leaders After the Use of the Atomic Bombs
Even after the use of the atomic bomb on Hiroshima and Nagasaki, the Japanese were still undecided on whether to surrender
There were two opposing plans for surrender
The plan with four conditions
1. A guarantee that the imperial family will continue to reign.
2. Disarmament of the armed forces by Japan herself.
3. Trial of war criminals by Japan herself.
4. Occupation of Japan to be limited to the minimum time and places
“Only on August 9, after withstanding months of blockade and bombardment, obvious preparations for invasion, two atomic bombs, and Soviet intervention, did the Big Six formulate terms for ending the war” (Frank, 344) Evidence shows that Japan was extremely unwilling to surrender at all costs. Even after the use of atomic weapons, Japan still argued about the details of how they should surrender. Therefore, without the use of Atomic weapons, the conclusion of the war could have taken years and could have yielded massive casualties on both sides. Japanese Foreign Minister wanted to surrender only under the first condition; a guarantee that the imperial family will continue to reign. At this time, there were still many factions, making terms of surrender hard to agree on.

66. The Japanese Surrender
The Japanese surrendered on September 2,
The ceremony took place on the USS Missouri accompanied by British ships in Tokyo Bay.
Japan agreed to a ceasefire and the release of POW’s.
Japan agreed to end all hostilities and acknowledge the authority of the U.S. Supreme Commander. The Japanese Prime Minister, Prince Higashi Kuni, broadcasted an appeal to his people to obey the terms of the surrender. Japan was forced to accept its defeat “squarely”.
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67. Imperial Rescript on Surrender
…”The enemy has begun to employ a new and most cruel bomb, the power of which to do damage is, indeed, incalculable, taking the toll of many innocent lives. Should we continue to fight, not only would it result in an ultimate collapse and obliteration of the Japanese nation, but also it would lead to the total extinction of human civilization.
Such being the case, how are We to save the millions of Our subjects, or to atone Ourselves before the hallowed spirits of Our Imperial Ancestors? This is the reason why We have ordered the acceptance of the provisions of the Joint Declaration of the Powers.
On August 15, 1945, Emperor Hirohito of Japan recorded a national radio address called the Imperial Rescript on Surrender which said that Japan would accept the Potsdam Declaration (unconditional surrender). This speech was interesting because it was the first time that the emperor addressed the common people. However, the actual speech made no direct reference to surrender. Instead, Hirohito said that Japan would accept the Potsdam Declaration. This speech showed Japanese pride because surrendering to Americans was the last thing a Japanese soldier wanted to do.
PRIMARY SOURCE -

68. Signing of the Terms of Unconditional Surrender by Japan
“As President of the United States, I proclaim Sunday, September the second, 1945, to be V-J Day--the day of formal surrender by Japan. It is not yet the day for the formal proclamation of the end of the war nor of the cessation of hostilities. But it is a day which we Americans shall always remember as a day of retribution--as we remember that other day, the day of infamy. From this day we move forward. We move toward a new era of security at home. With the other United Nations we move toward a new and better world of cooperation, of peace and international good will and cooperation. God's help has brought us to this day of victory. With His help we will attain that peace and prosperity for ourselves and all the world in the years ahead.
An excerpt (1 minute) from Truman’s announcement of Japanese surrender speech will play. Students can read along with the text above.
In Truman’s radio address to the American people after the signing of terms of unconditional surrender by Japan, Truman mentions V-J (Victory Japan day), the day of Japan’s surrender. On August 14, 1945, Japan signed the Potsdam Declaration. After six years of war, peace finally came. Truman mentions that God helped bring an American victory and looks forward to a prosperous future. This speech is very inspirational because he refers to Pearl Harbor – Day of Infamy, which was a devastating event for all Americans. Now America feels that it has gotten revenge and can look forward to the future. Truman address is reassuring to the American public because the Japanese surrender is a personal victory for every American.
Primary source audio clip - ftp://webstorage2.mcpa.virginia.edu/library/nara/hst/audiovisual/speeches/hst_1945_0901.mp3

69. Hindsight
Truman believed that if the atomic bomb was not successful, an invasion would be needed.
After the war, information concluded that Japan would have surrendered.
"Certainly prior to 31 December 1945, and in all probability prior to November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated."
In 1946 Bombing Survey concluded Japan would have surrendered even if the U.S. did not use the atomic bomb. Before the atomic bombs were dropped, the U.S. naval blockade proved to be very efficient. Also, America was inflicting great damages on Japan’s infrastructure, which would eventually result in Japan’s surrender.
However, Secretary Stimson, doubted that Japan's rulers would have accepted unconditional surrender if the home islands had not been invaded or if the atomic bomb had not been dropped. In any case, many American lives would have been lost by November 1, 1945 and after that date, the invasion of Kyushu would be underway. It is safe to say that the atomic bomb averted many American causalities and brought a successful end to World War II.