JAPANESE CODE-BREAKING IS REVEALED TO THOMAS E. DEWEY
F.D.R. CALLS OPPONENT DEWEY 'DESPERATE' AS THE THREAT OF POLITICAL GAIN BY TREACHERY BECOMES A POSSIBILITY An explosive A.Ms. (unsigned) by HARRY HOPKINS (1890-1946), a trusted deputy to President Franklin Roosevelt who directed New Deal relief programs before serving as Secretary of Commerce and as Roosevelt's chief foreign policy advisor and liaison to Allied leaders during World War II. In this 3pp. 4to. holograph memoir, 1944, Hopkins reveals that an unknown high-ranking American military officer had actually revealed the Navy's 'cracking' of Japanese codes in the pre-war years to THOMAS E. DEWEY (1902-1971), Roosevelt's adversary in the 1944 presidential race and a staunch isolationist. In his memo, titled 'Marshall Letter to Dewey', Hopkins sets forth the details of the revelation of the top secret 'Magic' code breaking to Dewey, and the ensuing panicked reaction by Army Chief of Staff GEORGE MARSHALL. Hopkins' account, in pencil, reads in part: '...One morning late in October 1944 I was visiting with General Marshal in his office. He told me that he had received information that someone in the armed services had given [Presidential candidate] Governor [Thomas E.] Dewey confidential and secret information relative our breaking the Jap codes. He stated he believed Dewey was given the factual information...Furthermore, it was his (Marshall's) belief that Dewey intended to state this fact publicly for political purposes...the disclosure of our method of our acquiring the information would be fatal to our military interests...Marshall stated that he had undertaken on his own behalf and without consulting anyone to write to Gov. Dewey...he asked Mr. Dewey in the first paragraph not to read further because he he would tell highly secret military information - unless he was prepared to keep it in strict confidence. Later that day I repeated this conversation to the President. While express[ing] no [?] of Marshall's action he said he felt confident Gov. Dewey would not for political purposes give military information to the enemy. 'My opponent must be pretty desperate if he is even thinking of using material like this.' The President [wondered] what officer or government official had been so faithless to his country as to give Governor Dewey this information...' An additional page of notes in another hand, headed 'HOPKINS', shows Hopkins' schedule at about the same time which included meetings with Marshall and the Joint Chiefs of Staff, as well as Gen. Brehon Somerville, Robert Patterson, and one John J. McCloy, one of Roosevelt's 'wise men' and Assistant Secretary of War under Henry Stimson, helping deal with issues such as Axis sabotage. Marshall's Oct. 25, 1944 top secret letter was delivered by an Army office to Dewey at during a secret meeting in Virginia. In it, Marshall pleaded with Dewey not to reveal the decoding secret, code named 'Magic' by the Army Signal Intelligence Service, which had cracked the codes early in 1941. 'You will understand the utterly tragic consequences if the present political debates regarding Pearl Harbor disclose to the enemy any suspicion of the vital sources of information we possess,' Marshall said to Dewey. 'The conduct of all operations in the Pacific are related in conception and to closely intercepted codes.' According to Col. Carter W. Clarke, who delivered Marshall's plea, Dewey balked at keeping silent and insisted that Roosevelt must have known about the Japanese plan to attack Pearl Harbor and that Marshall was simply trying to cover up for the president. 'Instead of being reelected, he ought to be impeached.' Clarke scheduled another meeting with Dewey, but the governor declared: '...he could not see me or anyone else alone, that he would not read a letter he could not keep and which he could not show to [and aide] or discuss...' Clarke said. Dewey and F.D.R. were bitter political rivals, and their campaigns were contentious. Nevertheless, Dewey never revealed the secret information he had been given, and Roosevelt won by a landslide of electoral votes. The identity of the traitor who revealed the top secret code breaking revelations has never been determined - indeed, Marshall's letter itself was not made public until 1981.