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1945: Ending the War

1945: Ending the War

Timeline Image: 
Sea full of ships under way

August 10, 1945

Japanese civilian and military leaders are still unable to agree on accepting the Potsdam Declaration's surrender terms. Emperor Hirohito instead breaks the tradition of imperial non-intervention in government and orders that surrender be accepted, provided that the Emperor be allowed to retain his position. General Groves reports that the second plutonium core would be ready for shipment on August 12 or 13, with a bombing possible on August 17 or 18. President Truman orders a halt to further atomic bombing until further orders are issued.

1945 Aug 17

J. Robert Oppenheimer warns Secretary of War Henry Stimson that:

Atomic weapons would improve qualitatively and quantitatively over coming years.
Adequate defenses against nuclear weapons would not be developed.
The US would not retain hegemony over nuclear weapons.
Wars could not be prevented even if better nuclear weapons were developed.


1945 Aug 14

Following leaflet bombing of Tokyo with surrender terms, Hirohito orders that an Imperial Edict accepting surrender be issued. At 2:49 p.m. (1:49 a.m. Washington time), Japanese news agency announces surrender.

1945 Aug 13

Secretary of War Henry Stimson recommends shipping the second plutonium core to Tinian Island. President Truman orders area firebombing resumed. Gen. Henry Arnold, US Army Air Force, launches the largest raid on Japan of the war with over 1000 B-29s and other aircraft, carrying 6000 tons of bombs.