the attack on hiroshima

8/14/2019 The Attack on Hiroshima

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EssentialEssential

QuestionQuestionWhat were Harry

Trumans motivations for

using the Atomic

Bomb against Japan in World War II?


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Nuclear Programs:Nuclear Programs:

GermanyGermanyGermany started experimenting withGermany started experimenting withNuclear Fission in 1938.Nuclear Fission in 1938.

German scientist Otto Hahn andGerman scientist Otto Hahn andFritz Strassman bombarded UraniumFritz Strassman bombarded Uraniumwith neutrons and discovered Bariumwith neutrons and discovered Barium

atoms.atoms.

Conclusion: Nuclear fission releasesConclusion: Nuclear fission releasesa massive amount of energya massive amount of energy


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GermanGermanexperimentalexperimental

nuclear pile atnuclear pile atHaigerlochHaigerloch


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Project AlsosProject AlsosU.S. investigation in 1945 determinedthat the Germans have not created asustained nuclear chain reaction.

By creating a chain reaction, theGermans could create a nuclear reactorfor nuclear power or absolutedestruction.

It is debated whether German scientistssabotaged their success of their nuclearprogram purposefully or whether theirestimates were simply inaccurate andinadequate.


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No Bomb for theNo Bomb for the

GermansGermansJune 1942 German atomic programslows down because Germany feltvictory in WWII was imminent.

U.S. and Britain were not aware thatthe Germans decided not to build abomb.

Japan also had an atomic program butwas not successful.

If Germany and Japan had created anatomic bomb, it would be used againstthe Allies.


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Failure of the GermanFailure of the German

Nuclear ProgramNuclear ProgramWhen Adolf Hitler was in power, Hitlerencouraged many top scientists to leave

Europe.

Heavy water was not easily accessible.

No known factories for the production ofnuclear missiles.

Paris Treaties of 1955


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Japanese AtomicJapanese Atomic

ProgramProgramThe Japanese atomic program was runby Empire of Japan in order to developa genshi bakudan or atomic bomb.

This project started around the sametime as the Manhattan Project.

Japan did not complete their atomicbomb by World War II.


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Hideki YukawaHideki Yukawa Hideki Yukawa was aJapanese theoreticalphysicist who was thefirst Japanese man towin the Nobel PeacePrize.

In 1935 Yukawapublished his theory ofmesons, which explainedthe interaction between

protons and neutrons.His writing quicklybecame a majorinfluence on research inelementary particles.


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Einsteins LetterEinsteins 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)


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The ManhattanThe Manhattan

ProjectProjectJune 1942, atomic-bomb project wascontrolled by War Department's Army Corpsof Engineers.

American and European physicists discoveredthat the fission of uranium could a powerfulweapon.Major General Leslie Groves named head ofthe project.At the height of construction in mid 1944,the Project employed nearly 129,000 people.No other nation in the world had the massiveindustrial capacity to make this possible .


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Project Cont.Project Cont.To disguise this ultra-secret project,the Corps created a ManhattanEngineer District, with a headquartersinitially based in New York City.

Most work done at Los Alamos, NewMexico

Gadget (Trinity) on July 16, 1945


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Robert J.Robert J.

OppenheimerOppenheimerWhen 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.


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Robert J.Robert J.Oppenheimer cont.Oppenheimer cont.

Late in 1942, Gen. Groves chose physicist J.Robert Oppenheimer to head a new laboratorydevoted to the designing atomic bombs.

Oppenheimer recommended a remote site inNew Mexico for the new facility, where manyfamous scientists could work together incomplete secrecy.

From a wealthy N.Y. Jewish family.

Ties with Communism.


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Letter to HarryTrumanApril 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


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Los Alamos National

LaboratoryLos Alamos National Laboratory is one ofthe two laboratories in the United Stateswhere classified work towards the designof nuclear weapons have been undertaken.The other location is Lawrence LivermoreNational Laboratory.

During the Manhattan Project, Los Alamoswas home to thousands of employees.

The first nuclear test was located nearAlamogordo, New Mexico, under code nameTrinity on July 16, 1945.


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Project SuccessProject SuccessTwo atomic bombs were made,Little Boy and Fat Man.

Scientists at Los Alamos were notfully confident in the Fat Manbomb.

Bombs designed to create anaccurate and symmetricalimplosion.


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TrinityTrinity

July 16, 1945July 16, 1945


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Fission BombFission Bomb


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Fat Man andFat Man and

Little BoyLittle BoyFat

Man

LittleBoy


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New Weapons inNew Weapons in

World War IIWorld War IIDuring the last stages of the war,two new weapons were introduced:

the long-range rocket and the atomicbomb.

Throughout the war, most weapons

were an improved version of theweapons used in World War I.

Atomic bomb = absolute destruction.


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Russian Influences onRussian Influences onDevelopment of theDevelopment of the

Atomic BombAtomic Bomb

The US carefully considered Russia inthe development of the Atomic Bomb.

General Groves viewed the Soviet Unionas one of Americas worst enemies.

Trumans advisors convinced him that ifthe Atom bomb was used, it would keepthe USs enemy Russia at bay.

Postwar use of the bomb as a bargainingchip for territory was highly valued.


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A Chance forA Chance for

peace?peace?One week before Roosevelt's death,

Japanese Prime Minister KuniakiKoiso and his cabinet resigns.

Second resignation of Prime Ministerin two years.

Japan believed unconditionalsurrender was not tolerable.

Kantaro Suzuki was named new PrimeMinister.


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Battle of OkinawaBattle of OkinawaKnown as Typhoon ofSteelLargest amphibiousassault in Pacific of theWar.Operation Downfall invasion of main islandsin Japan48,000 Americans died.150,000 Japanesecivilians died.Japanese propagandaviewed Americans asbarbarians. This gave the Japanese themindset of never surrendering to an American.


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Uses for the BombUses for the Bomb

Against Germany or Japan

General Groves believed it could end WorldWar II.

$2 billion used to build the bomb. Not usingit 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


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Debate over theDebate over the

Bomb:Bomb:American SupportAmerican SupportAmericans were suffering manycasualties and the Japanese wereshowing no signs of possiblenegotiation.

A cease fire was non-negotiable.

If the United States dropped theatomic bomb, surrender and peace

would probably occur.


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Potsdam DeclarationPotsdam Declaration

July 26, 1945July 26, 1945Key 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.


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PotsdamPotsdamDeclaration Cont.Declaration Cont.

1. Japan would be occupied until the declaration wassigned.

2. The Japanese army wouldbe allowed to return home.

3. Once the declaration was

met, allied troops would bewithdrawn.4. Japan shall be permitted

to maintain such industriesas will sustain her economyand permit the exaction of just reparations in kind, butnot those which would enable her to re-arm for war.To this end, access to, as distinguished from controlof, raw materials shall be permitted. Eventual Japaneseparticipation in world trade relations shall be permitted.


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Japans Response to theJapans Response to thePotsdam DeclarationPotsdam DeclarationJapans response was ambiguous.Before Japan could agree to any surrender, thetop military officials had to figure out a way tosatisfy many different groups inside Japan.Japanese official Suzuki used the wordmokusatsu which had a few different Englishtranslations.The US and the US newspapers interpreted theword to mean reject when in fact it could havemeant something different.The apparent rejection of the Declarationdefinitely sped up the process of using theatomic bombs.


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UnconditionalUnconditional

SurrenderSurrenderEstablished at the CasablancaConference early 1943.

Popular because war aims were clear.

Gained Soviet and American support.

Prevents country from resurging topower (Germany).


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Japanese View ofJapanese View ofUnconditionalUnconditional

SurrenderSurrenderEmperor Hirohito was

totally againstunconditional surrender.Americans viewedHirohito as a symbol ofmilitary aggressionUnconditional surrender

destruction ofdivine monarchy.


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Emperor HirohitoEmperor HirohitoThe atomic bomb convinced the Emperorto break the deadlock of Japansgenerals and accept the PotsdamDeclaration

He gave three reasons, "a collapse ofdomestic morale and two militaryconcerns: inadequate preparation toresist the invasion and the vastdestructiveness of the atomic bomb and

the air attacks (Frank, 345).The atomic bomb was given as the mainreason for the surrender of Japan


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Roosevelts InfluencesRoosevelts Influenceson Trumanon Truman

Even though Truman and Roosevelt didnot get along, Roosevelts legacyremained in power.

Roosevelts former advisors found iteasy to mold the new president Trumansforeign policy and his feelings towardthe Soviet Union.

Kissinger said, Soviet policies were explained to Truman in inherent bad faith model.

These heavy influences made thedecision to drop the atom bomb very

optimal.


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Trumans MotivationsTrumans Motivations

It cost the US $20 billion (intodays dollars) to build the atomicbomb.

It cost the US $20 billion (intodays dollars) to build the atomicbomb.

The use of the atomic bombs inending World War 2 preventedendless investigations of theTruman administration.


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Trumans MotivationsTrumans MotivationsCont.Cont.

Many historians believe that a mainreason for the use of the bomb wasretaliation for the surprise and brutalattack on Pearl Harbor.

After the bomb was dropped onHiroshima, 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 POWS were mistreated


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Saving Lives bySaving Lives by

Using the BombUsing the BombNon-combatants were dying throughoutAsia at the rate of 200,000 permonth.

The complete naval blockade of Japanwould have resulted in hundreds ofthousands of deaths due tomalnutrition, dehydration, and famine.

The atomic bomb saved thousands ofAmerican soldiers lives


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Invading Japan?Invading Japan?If America did invade Japan, manyAmericans would have died.

Secretary of

State JamesByrnes claimed500,000.

Total combat

deaths afterfour years ofwar 292,000.


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The Beginning of theThe Beginning of the

End of Imperial JapanEnd of Imperial Japan By 1945, a Japanese victory would not bepossible.

Use of kamikaze (divine wind) attacks damaged about50 U.S. ships and sunk 17 during January 4 13 1945.

Many Japanese soldiers jumped off cliffs instead ofsurrendering 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 November1945.


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Japanese SupportJapanese SupportSome Japanese historians supportedthe dropping of the atomic bombs.

Salvation in the atomic bombing.

Koichi Kido We of the peaceparty were assisted by the atomicbomb in our endeavor to end thewar.

Hisatsune Sakomizu Goldenopportunity given by heaven to endthe war.


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Japan and theJapan and the

Soviet UnionSoviet UnionThere was a slight chance that

peace could come through Moscow.

Japan desperately sought help fromStalin to fight defeat.

Japan wanted a conditionalsurrender with Allies.

d h


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U.S. and theU.S. and theSoviet UnionSoviet Union

Soviet Union played alarge role in the useof the atomic bomb.Growing tensions betweenU.S. and Soviet Union -puppet governments inEastern Europe.Stalin started a Sovietatomic bomb project in1942.Soviets helped defeatGermany, but Stalin wasnot popular with the Allies.

h


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The Soviet UnionThe Soviet Unionin the Pacificin the Pacific

WarWarAs Germany weakened near defeat,U.S. wanted the Soviet Union to enterthe Pacific War.

Yalta Conference Feb. 1945, Stalinpromises to enter Pacific War 2-3months after Germany surrenders.

U.S. leaders start to have secondthoughts on the Soviet Unions entrance

into the Pacific War.


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Magic & UltraMagic & UltraMagic U.S. discovers Japan wantsSoviet help.

Unconditional surrender was notpossible.

Ultra Japan willing to fight until

the end.

Further limited hope of negotiationwith the Japanese.


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Interim CommitteeInterim CommitteeThe Interim Committee on post-waratomic policy discussed dropping the bombon Japan without any formal warning.

May 31, 1945 meeting was held withStimson (Sec. of War), James Byrnes(Sec. of state), and scientific advisersheld by Dr. Robert Oppenheimer.

Committee decided not to formally warn

Japan for the Hiroshima dropping.U.S. needed to shock Japanese tosurrender, so a warning was out ofquestion.


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Opposition to theOpposition to theInterim CommitteeInterim CommitteeLeo Szilard and other ManhattanProject scientists believed Japanshould be warned.Without a formal warning would beimmoral in the eyes of the world.

Also, scientists believed U.S. should

tell Soviets before using the war postwar arms race.

Chicago group petitioned toPresident Truman.

bl


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Possible TargetPossible TargetLocationsLocations

The target committee at Los Alamos fromMay 10 11, 1945, recommended Kyoto,Hiroshima, Yokohama, and arsenal at Kokuraas possible targets.

The psychological effects on the Japanesecitizens were important to the committeemembers.

The target location for the detonation ofthe bomb should be spectacular forinternational recognition.

Kyoto, Hiroshima, Kokura, and Niigata.

T T


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TrumansTrumansTrue BeliefsTrue 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.


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Ulterior Motives forUlterior Motives for

Atomic Bombs?Atomic Bombs?


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Official OrderOfficial Order

To Drop BombTo Drop Bomb1. Stimson (Sec. of War) and Byrnes(Sec. of State) advised Truman to usethe bomb. Spring and summer of 1945,

Truman approves decision.

2. Decision was noninterference.

3. Lt. Gen. Carl Spaatz requested awritten order.

4. Official order was issued on July 25 th .


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SuccessSuccessAt 2 PM, just a few hours after the bombwas dropped on Hiroshima, General LeslieGroves called Dr. Robert Oppenheimer totell him of the weapons mass success

Groves said Apparently it went with atremendous bang.

Right after the tremendous success with theHiroshima bombing, Every effort is beingdevoted to their next objective (Nagasakithree days later)

After Nagasaki it was mentioned that therewill be a following objective implying thatthere could be a third bombing


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The Atomic Bomb atThe Atomic Bomb at

HiroshimaHiroshima


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Hiroshima DuringHiroshima During

World War IIWorld War IIHiroshima, Japan had reached a populationof over 381,000.

Due to evacuations, the city populationdropped to 255,000 at the time of theattack.

The citys building construction consistedof several reinforced concrete buildingsand lighter structures such as smallwooden workshops and houses.


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The Enola GayThe Enola GayOn August 6, 1945, the B-29 Enola Gay,under colonel Paul Tibbits left Tinian airbasein the West Pacific.

The six hour flight went exactly asexpected.

The bomb wasarmed midwayand clearweatherpermitted foraccuracy.


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Hiroshima BeforeHiroshima Before

The Atomic BombThe Atomic Bomb


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Hiroshima AfterHiroshima After

The Atomic BombThe Atomic Bomb


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The Mushroom CloudThe Mushroom Cloud8:15 AM, The LittleBoy was droppedover the center ofHiroshima

It exploded about2,000 ft. above thecity and had a blastthe equivalent to 13kilotons of TNT.

Due to radiation,approximately152,437 additionalpeople have died.

N ki D iN ki D i


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Nagasaki DuringNagasaki DuringWorld War IIWorld War II

Nagasaki was one of the largestseaports in southern Japan.

The city was important during the warbecause of great industrial activity.

Most residences and industrial buildings weremade of wood.

Since the city had been permitted to growwithout any strict zoning laws, most buildingsand residences were constructed closely toeach other.

Formal WarningFormal Warning


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Formal WarningFormal Warningto Japanto Japan

The leaflets calledfor a petition to theEmperor of Japan tostop the war andagree to thirteenconsequences of anhonorable surrender.

The leaflets calledfor a petition to theEmperor of Japan tostop the war andagree to thirteenconsequences of anhonorable surrender.

Sample Leaflet

On August 10, 1945thousands of leafletswere dropped over thecity of Nagasaki


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BockscarBockscarSometimes called Bocks car.

B-29 bomber Superfortress, flown by MajorCharles W. Sweeney droppedthe Fat Man on August 9, 1945.

The Bockscar did didn't haveenough fuel to return toTinian or Iwo Jima,so Major Sweeney flew

the aircraft to Okinawafor an emergencylanding with practicallydry fuel tanks.

Th B biTh B bi


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The Bombing:The Bombing:NagasakiNagasaki

Before After


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Japanese LeadersJapanese Leaders


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Japanese LeadersJapanese LeadersAfter the Use of theAfter the Use of the

Atomic BombsAtomic BombsEven after the use of the atomic bomb onHiroshima and Nagasaki, the Japanese werestill 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 byJapan herself.3. Trial of war criminals by Japan herself.4. Occupation of Japan to be limited to theminimum time and places

Th JTh J


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The JapaneseThe JapaneseSurrenderSurrender

The Japanesesurrendered onSeptember 2,1945.

The ceremonytook place onthe USS Missouri accompanied by

British ships inTokyo Bay.

Japan agreed to a ceasefire and the releaseof POWs.


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Imperial RescriptImperial Rescript

on Surrenderon SurrenderThe 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.

Signing of the TermsSigning of the Terms


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Signing of the TermsSigning of the Termsof Unconditionalof Unconditional

Surrender by JapanSurrender 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.


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HindsightHindsightTruman believed that if the atomicbomb was not successful, an invasionwould be needed.

After the war, information concludedthat 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 "

the attack on hiroshima

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