Chronology of the Decision to Use the Bomb

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Chronology of the Decision to Use the Bomb

• The official order states
• "The 509 Composite Group, 20th Air Force will
  deliver its first special bomb as soon as the
  weather will permit visual bombing after about 3
  August 1945 on one of the targets Hiroshima,
  Kokura, Niigata, and Nagasaki."

Yi-Ren Chen Hist 5N April 11th 2004
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• March 25
• At the urging of Leo Szilard, Albert Einstein
  signs a letter of introduction of Szilard to
  President Roosevelt. Szilard wishes to warn
  Roosevelt of the post-war dangers of a nuclear
  arms race if the atomic bomb is used against
  Japan. The letter states The terms of secrecy
  under which Dr. Szilard is working at present do
  not permit him to give me information about his
  work however, I understand that he now is
  greatly concerned about the lack of adequate
  contact between scientists who are doing this
  work and those members of your Cabinet who are
  responsible for formulating policy. In the
  memorandum accompanying the letter, Szilard
  wrote our demonstration of atomic bombs will
  precipitate a race in the production of these
  devices between the United States and Russia and
  that if we continue to pursue the present course,
  our initial advantage may be lost very quickly in
  such a race.

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• April 12
• Franklin Roosevelt dies, and Harry Truman becomes
  the 33rd President of the United States.
• April 25
• Secretary of War Stimson and General Groves brief
  President Truman on the bomb. In this briefing,
  Groves insists that Japan had always been the
  target of the bombs use.
• April 25
• Joint Chief Planners advise Joint Chiefs of Staff
  that unless a definition of unconditional
  surrender can be given which is acceptable to the
  Japanese, there is no alternative to annihilation
  and no prospect that the threat of absolute
  defeat will bring about capitulation.

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• April 27
• The Target Committee meets for the first time to
  decide which Japanese cities to target with the
  atomic bomb. By the end of May the following
  cities are selected Kyoto, Hiroshima, Kokura and
  Niigata. See minutes of the second meeting of
  the Target Committee in Related Sites.
  Eventually Kyoto is replaced by Nagasaki and the
  listed cities are spared further conventional
  bombing by the American Army Air Force.
• April 29
• In a report entitled Unconditional Surrender, the
  Joint Intelligence Committee informs the Joint
  Chiefs of Staff that numbers of informed
  Japanese, both military and civilian, already
  realize the inevitability of absolute defeat.
• May 8
• War in Europe ends.

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• May 9
• The Interim Committee meets for the first time.
  Its purpose is to study and report on the whole
  problem of temporary war controls and later
  publicity, and to survey and make recommendations
  on post war research, development and controls,
  as well as legislation necessary to effectuate
  them. The Interim Committee appoints a
  Scientific Panel, which included Oppenheimer,
  Lawrence, Fermi and Compton.
• May 25
• Leo Szilard visits White House with letter of
  introduction from Albert Einstein to warn
  President Truman of the dangers atomic weapons
  pose for the post-War world and to urge him not
  to authorize use of atomic weapons against Japan.
  Szilard is referred Matthew J. Connelly,
  Trumans appointments secretary, to James Byrnes
  in Spartanburg, South Carolina.

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• May 28
• Assistant Secretary of War John J. McCloy argues
  to Secretary of War Stimson that the term
  unconditional surrender should be dropped
  Unconditional surrender is a phrase which means
  loss of face and I wonder whether we cannot
  accomplish everything we want to accomplish in
  regard to Japan without the use of that term.
• May 28
• In a State Department Memorandum of Conversation,
  Acting Secretary of State Joseph Grew describes a
  meeting with President Truman that day. Grew
  writes The greatest obstacle to unconditional
  surrender by the Japanese is their belief that
  this would entail the destruction or permanent
  removal of the Emperor and the institution of the
  Throne. If some indication can now be given the
  Japanese that they themselves, when once
  thoroughly defeated and rendered impotent to wage
  war in the future will be permitted to determine
  their own future political structure, they will
  be afforded a method of saving face without which
  surrender will be highly unlikely.

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• May 31
• The Interim Committee agrees that the most
  desirable target would be a vital war plant
  employing a large number of workers and closely
  surrounded by workers houses. Among those
  agreeing is James Conant, the president of
  Harvard University.
• May 31
• The Office of Strategic Services (OSS) reports on
  receiving a Japanese peace feeler through a
  Japanese diplomat stationed in Portugal. The
  Japanese diplomat says that the actual terms are
  unimportant so long as the term unconditional
  surrender is not used.
• June 1
• Interim Committee makes formal decision decides
  not to warn the civilian populations of the
  targeted cities.

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• June 11
• The Franck Committee on the social and political
  implications of the atomic bomb, headed by Nobel
  Laureate James Franck, issues a report advising
  against a surprise atomic bombing of Japan. The
  report states, If we consider international
  agreement on total prevention of nuclear warfare
  as the paramount objectivethis kind of
  introduction of atomic weapons to the world may
  easily destroy all our chances of success. The
  report correctly predicts that dropping an atomic
  bomb will mean a flying start toward an
  unlimited armaments race.
• June 14
• The Franck Committee Report with its
  recommendation that bomb be demonstrated to Japan
  before being used on civilians is taken by
  Compton to Los Alamos, and copies were given to
  Fermi, Lawrence and Oppenheimer. June 16
• Compton, Fermi, Lawrence and Oppenheimer
  conclude We can propose no technical
  demonstration likely to bring an end to the war
  we see no acceptable alternative to direct
  military use.

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• June 17
• McCloy tells Stimson that there were no more
  cities to bomb, no more carriers to sink or
  battleships to shell we had difficulty finding
  targets.
• June 18
• Admiral Leahy makes diary entry noting, It is my
  opinion at the present time that a surrender of
  Japan can be arranged with terms that can be
  accepted by Japan and that will make fully
  satisfactory provision for Americas defense
  against future trans-Pacific aggression. He
  also notes that General Marshall believes that an
  invasion of Kyushu, the southern-most Japanese
  island, will not cost us in casualties more than
  63,000 of the 190,000 combatant troops estimated
  as necessary for the operation. This may be
  compared to later estimates, after the atomic
  bombings, of 500,000 to 1,000,000 American lives
  saved.

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• June 20
• A meeting of the Supreme War Direction Council
  before Emperor Hirohito is held on the subject of
  ending the war. According to the U.S. Strategic
  Bombing Survey, the Emperor, supported by the
  premier, foreign minister and Navy minister,
  declared for peace the army minister and the two
  chiefs of staff did not concur.
• June 26
• Stimson, Forrestal and Grew agree that a
  clarification of surrender terms should be issued
  well before an invasion and with ample time to
  permit a national reaction to set in. The three
  agreed that Japan is susceptible to reason.
• July 10
• At a meeting of the Supreme War Direction
  Council, Emperor Hirohito urges haste in moves to
  mediate the peace through Russia.

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• July 13
• Washington intercepts and decodes a cable from
  Japanese Foreign Minister Shigenori Togo to his
  Ambassador in Moscow that states, Unconditional
  surrender is the only obstacle to peace.
• July 15
• President Truman lands at Antwerp on his way to
  Potsdam meeting. Byrnes has convinced him to
  drop Article 12 of the Potsdam Declaration, which
  had provided assurance that the Emperor would be
  allowed to retain his throne as a constitutional
  monarch.
• July 16
• Trinity test, a plutonium implosion device, takes
  place at 52945 a.m. mountain war time at
  Alamogordo, New Mexico. It is the worlds first
  atomic detonation.

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• July 17
• President Truman at Potsdam writes in his diary,
  Just spend sic a couple of hours with Stalin.
  Hell be in the Jap War on August 15th. Fini
  Japs when that comes about.
• July 21
• President Truman approves order for atomic bombs
  to be used
• July 23
• UK Prime Minister Winston Churchill remarks,
  It is quite clear that the United States do
  not at the present time desire Russian
  participation in the war against Japan.
• July 24
• Walter Brown, special assistant to Secretary of
  State Byrnes, writes in his journal that Byrnes
  was now hoping for time, believing after atomic
  bomb Japan will surrender and Russia will not get
  in so much on the kill, thereby being in a
  position to press claims against China.

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• July 24
• Secretary of War Henry Stimson passes on orders
  for atomic attack.
• July 25
• General Carl Spatz, commander of the United
  States Army Strategic Air Forces, receives the
  only written order on the use of atomic weapons
  from acting Chief of Staff, General Thomas Handy.
• July 26
• Potsdam Declaration calls upon Japanese
  government to proclaim now the unconditional
  surrender of all Japanese armed forces. The
  alternative, the Declaration states, is prompt
  and utter destruction.
• July 26
• Forrestal secret diary states, In the past days
  Sato in Moscow has been sending the strongest
  language to the Foreign Office at Tokyo his
  urgent advice for Japan to surrender
  unconditionally. Each time the Foreign Minister,
  Togo, responds by saying that they want Sato to
  arrange for the Russians to receive Prince Konoye
  as a special representative of the Emperor to
  Moscow. Satos persistent reply to these
  messages was that this is a futile hope, that
  there is no possibility of splitting the concert
  of action now existing between Great Britain, the
  United States and Russia.

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• July 28
• Japan rejects Potsdam Declaration.
• August 6
• The world's second atomic bomb, Little Boy, a
  gun-type uranium bomb, is detonated 1,900 feet
  above Hiroshima, Japan. It has a yield of
  approximately 15 kilotons TNT. Some 90,000 to
  100,000 persons are killed immediately about
  145,000 persons will perish from the bombing by
  the end of 1945.
• August 8
• Soviet Union informs Japan that it is entering
  the war.

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• August 9
• At 944 a.m. Bockscar, a B-29 carrying Fat Man,
  the world's third atomic bomb, arrives at its
  primary target, Kokura. The city is covered in
  haze and smoke from an American bombing raid on a
  nearby city. Bockscar turns to its secondary
  target Nagasaki. At 1102 a.m. the world's third
  atomic bomb explosion devastates Nagasaki, the
  intense heat and blast indiscriminately
  slaughters its inhabitants

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• August 9
• President Truman speaks to the American people
  via radio broadcast He states, The world will
  note that the first atomic bomb was dropped on
  Hiroshima, a military base. That was because we
  wished in the first instance to avoid, in so far
  as possible, the killing of civilians. The
  official Bombing Survey Report stated Hiroshima
  and Nagasaki were chosen as targets because of
  their concentration of activities and
  population. More than 95 percent of those
  killed at Hiroshima and Nagasaki were civilians.
• August 9
• Atomic bomb dropped on Nagasaki.
• August 9
• Soviet Union begins its offensive against Japan
  in Manchuria.
• August 14
• Japan surrenders.

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• Bibliography
• http//www.trumanlibrary.org/teacher/abomb.htm
• www.willamette.edu/cla/wviews/hiroshima.html
• www.socialstudieshelp.com/Lesson_95_Notes.htm
• www.colorado.edu/AmStudies/lewis/2010/atomic.htm
• History 5N readings, April 12 McGeorge,
  Berstein, Walzer.

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