740.00119 P.W./12–2945

The War Department to the Department of State
OPD 336 TS

Attention: Japan—Korea Economics Division

Subject: Request for Information on Cyclotrons in Japan

Receipt is acknowledged of your letter of 10 December 194573 enclosing a copy of dispatch No. 517/45 dated 27 November 1945 from [Page 1015] the Minister of Australia74 concerning the reported destruction of cyclotrons in Japan by order of the Supreme Commander for the Allied Powers.
In reply to your request for information of the facts of the destruction and the justification therefore, the following extract from the press conference of the Secretary of War of 14 December 1945 is quoted:

Press: Mr. Secretary, if no more questions on this, I have one on the destruction of the cyclotrons in Japan. MacArthur said your office ordered that.

Mr. Patterson: That is quite correct. I personally never saw the message but there was nothing strange about that because hundreds of messages go out of here from the Secretary of War that do not come to my personal notice. In this particular case, I believe that the matter was not handled with the thorough consideration that the matter warranted and that the sending of that particular message was a mistake, but in the theater to General MacArthur it was a directive and he took the proper action based upon the message. I am not certain what the answer would have been if the matter had received the thorough consideration that it should have had.

Press: Is anyone being disciplined over it, Mr. Secretary?

Mr. Patterson: No, I can make argument both ways on that question. You can see it was a case of mistake in the War Department.”

The following is suggested as a possible reply to the Minister of Australia:75

“General MacArthur was directed to destroy the Japanese cyclotrons in a radio message sent in the name of the Secretary of War. That message was dispatched without having been seen personally by the Secretary and without its having been given the thorough consideration which the subject deserved.

“While the officer who originated it felt that the action directed was in accordance with the War Department’s established policy of destroying Japan’s war potential, the dispatch of such a message without first investigating the matter fully was a mistake, which is regretted by the War Department.”

For the Secretary of War:
R. L. Vittrup

Colonel, GSC
  1. Not printed.
  2. Ante, p. 1002.
  3. For Department’s reply on January 29, 1946, see footnote 67, p. 1011.