President Truman Discusses the Bomb at Potsdam, July 1945
HS Truman diary, July 17, 18, and 25,1945, President's Secretary's Files, Papers of the President, Truman Library, Independence, Mo.

 

[Potsdam] July 17, [19]45

Just spent a couple of hours with Stalin. Joe Davies called on Maiski and made the date last night for noon today. Promptly a few minutes before twelve I looked up from the desk and there stood Stalin in the doorway. I got to my feet and advanced to meet him. He put out his hand and smiled. I did the same[,] we shook[,] I greeted Molotov and the interpreter, and we sat down. After the usual polite remarks we got down to business. I told Stalin that I am no diplomat but usually said yes & no to questions after hearing all the argument [sic]. It pleased him. I asked him if he had the agenda for the meeting. He said he had and that he had some more ques­tions to present. I told him to fire away. He did and it is dynamite—but I have some dynamite too which I am not exploding now. He wants to fire [Generalissimo Fran­cisco] Franco [the Spanish fascist dictator], to which I wouldn't object and divide up the Italian colonies, and other mandates, some no doubt that the British have. Then he got on the Chinese situation[,] told us what agreements had been reached and what was in abeyance. Most of the big points are settled. He'll be in the Jap War on August 15th. Fini Japs when that comes about. We had lunch[,] talked socially[,] put on a real show drinking toasts to everyone, then had pictures made in the back yard. I can deal with Stalin. He's honest—but smart as hell.

 

[Potsdam] July 18, 1945

At breakfast with nephew Harry, a sergeant in the Field Artillery [in which Truman had served as a Captain during World War I]. He is a good soldier and a nice boy. They took him off [the troopship] Queen Elizabeth at Glasco [Glasgow] and flew him here. Sending him home Friday. Went to lunch with P.M. [British Prime Minister Winston Churchill] at 1:30 walked around to British Hqrs [Headquarters]. Met at the gate by Mr. Churchill. Guard of honor drawn up. Fine body of men Scottish Guards Band played the Star Spangled Banner. Inspected Guard and went in for lunch. P.M. & I ate alone. Discussed Manhattan [Project] (it is a success). Decided to tell Stalin about it. Stalin had told P.M. of telegram from Jap Emperor asking for peace. Stalin also read his answer to me. It was satisfactory. Believe Japs will fold up before Russia comes in.

I am sure they will when Manhattan appears over their homeland. I shall inform Stalin about it at an opportune time. Stalin's luncheon was a most satisfactory meeting. I invited him to come to the U.S. Told him I'd send the Battleship Missouri for him if he'd come. He said he wanted to cooperate with U.S. in peace as we had cooperated in War but it would be harder. Said he was grossly misunderstood in the U.S. and I was misunderstood in Russia. I told him that we each could help to remedy that situation in our home countries and that I intended to try with all I had to do my part at home. He gave me a most cordial smile and said he would do as much in Russia.

We then went to the conference and it was my job to present the Ministers' proposed agenda. There were three proposals and I banged them through in short order, much to the surprise of Mr. Churchill. Stalin was very much pleased. Churchill was too after he had recovered. I'm not going to stay around this terrible place all summer just to listen to speeches. I'll go home to the Senate for that.

 

[Potsdam] July 25, 1945

We met at 11 a.m. today. That is Stalin, Churchill and the U.S. President. But I had a most important session with Lord Mountbatten & General Marshall before that. 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.

Anyway we "think" we have found the way to cause a disintegration of the atom. An experiment in the New Mexico desert was startling—to put it mildly. Thirteen pounds of the explosive caused the complete disintegration of a steel tower 60 feet high, created a crater 6 feet deep and 1,200 feet in diameter, knocked over a steel tower 1/2 mile away and knocked men down 10,000 yards away. The explosion was visible for more than 200 miles and audible for 40 miles and more.

This weapon is to be used against Japan between now and August 10th. I have told the Secretary], of War, Mr. [Henry] Stimson to use so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless, and fanatic, we as the leader of the world for the common welfare cannot drop this terrible bomb on the old Capital [Kyoto] or the new [Tokyo].

He & 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. I'm sure they will not do that, but we will have given them the chance. It is certainly a good thing for the world that Hitler's crowd or Stalin's did not discover this atomic bomb. It seems to me to be the most terrible thing ever discovered, but it can be made the most useful.