Roosevelt's letter to Groves

June 29, 1943

My dear General Groves:

I have recently reviewed with Dr. Bush the highly important and secret program of research, development and manufacture with which you are familiar. I was very glad to hear of the excellent work which is being dome in a number of places in this country under your immediate supervision and the general direction of the Committee of which Dr. Bush is Chairman. The successful solution of the problem is of the utmost importance to the national safety, and I am confident that the work will be completed in as short a time as possible as the result of the wholehearted cooperation of all concerned.

I am writing to you as the one who has charge of all the development and manufacturing aspects of this work. I know that there are several groups of scientists working under your direction on various phases of the program. The fact that the outcome of their labors is of such great significance to the nation requires that this project be even more drastically guarded than other highly secret war developments. As you know, I have therefore given directions that every precaution be taken to insure the security of your project. I am sure the scientists are fully aware of the reasons why their endeavors must be circumscribed by very special restrictions. Nevertheless, I wish you would express to them my deep appreciation of their willingness to undertake the tasks which lie before them in spite of the possible dangers and the personal sacrifices involved. In particular, I should be glad to have you communicate the contents of this letter to the leaders of each important group. I am sure we can rely on the continued wholehearted and unselfish labors of those now engaged. Whatever the enemy may be planning, American Science will be equal to the challenge. With this thought in mind, I send this note of confidence and appreciation.

Very sincerely yours,


Brigadier General L. R. Groves,

Room 5120, New War Department Building,

21st and Virginia Avenue, N. W.,

Washington, D. C.