I think it is very important that I should have a talk with you as soon as possible on a highly secret matter. I mentioned it to you shortly after you took office but have not urged it since on account of the pressure you have been under.

As Secretary of State (1929–1933) under Republican President Herbert Hoover he articulated the Stimson Doctrine which announced American opposition to Japanese expansion in Asia. Roosevelt. During World War II he took charge of raising and training 13 million soldiers and airmen supervised the spending of a third of the nation's GDP on the Army and the Air Forces helped formulate military strategy and took personal control of building and using the atomic bomb.