Foreign Relations of the United States, 1947, General; The United Nations, Volume I

Department of State Atomic Energy Files

Memorandum by Mr. Edmund A. Gullion to the Under Secretary of State (Lovett)

top secret

[Washington,] August 21, 1947.

The following is some background for that item of the Committee of Three agenda, for Thursday morning, August 21,¹ which refers to the need for an estimate of the date by which other countries may have developed atomic weapons.

1. The needs for such an estimate are many and obvious; e.g., our conduct of negotiations in United Nations, and our diplomatic negotiations across the board, would be affected by Russian production schedules of the bomb. Certain private groups in this country are pressing for abandonment of the negotiations and formation of a group of powers into an atomic alliance without Russia, on the theory that Russian production will begin next year. The Service Departments will, of course, have their own obvious interests in the Russian time schedule.

2. There does not appear to be any authoritative or precise estimate. The recent report of the Commission on Universal Training assumes “not less than 4 and not more than 10 years” as the period during which the US may be immune from attack. At the time of the Potsdam Conference this question was put to leading scientists and industrialists by Secretary Stimson’s Advisory Committee: “How long would it take Russia to produce an atomic bomb with or without complete blueprints of our production plans, with some consideration of German technical assistance?” The general consensus of opinion was a minimum of 5 and a maximum of 20 years. Many scientists now claim that the minimum figure should be given more serious consideration. They reason that it took the United States, with its almost unrestricted resources, three years to build the first atomic bomb. As an absolute minimum, assume that it would take the Russians the same time, which would be about Potsdam plus three, or, say, the summer of 1948.

Of course the question is very intricate, depending for example on whether the Russians are concentrating on plutonium or U-235 and on their uranium availabilities, as well as on their industrial facilities.

[Here follow suggestions with respect to organization of atomic energy intelligence functions.]

1. No record of the meeting under reference has been found in the files of the Department of State.