The Potsdam Conference: July 31st 1945 – Settling The Polish Question

Throughout his entire stay at Babelsberg, President Truman’s personal and official messages – including those from the War Department in Washington – arrived just down the street at the Army message center at today’s S-Bahn Griebnitzsee train station.

All correspondence addressed to the President was immediately decoded upon arrival and then taken to the ‘Little White House’ where they were delivered to the officers on duty in the Map Room, before they were then finally given to the President.

Late last night, another urgent top-secret cable to Truman was received and decoded, but held for delivery until this morning. When the President woke up, he came down to breakfast and read:

“The time schedule on Groves’ project is progressing so rapidly that it is now essential that the statement for release by you be available no later than Wednesday, 1 August…”

Time had now run out and the final decision to use the atomic bomb was now urgently needed.

For Truman, there were two options: First, go ahead with the invasion of Japan in early November and risk between thirty to fifty thousand American casualties, which was what the United States Army Chief of Staff George Marshall had projected on June 18 when Truman authorized ‘Operation Downfall’. Or second, deploy the atomic bomb and avoid the invasion, the ground war, and never seeing Marshall’s projections ever come to fruition.

“In order to end the War and save American lives, the bomb had to be used.”

On this day in 1945, at 7:48AM Berlin time, President Truman turned over the pink message from Washington and wrote large and clear with a lead pencil on the backside:

Reply to your 41011 suggestions approved.

Release when ready but not sooner than August 2.

The decision had now been made to use the most terrible weapon ever created on what would be two densely populated cities in Japan. In his message to the Secretary of War, Truman did not put any limitations on the use of the atomic bomb, which meant that its release was now up to the military until he felt it was time to put its use back into his control.