5GTKGU+8 8QNWOG 9GUV9KPF%NGCT West Wind Clear • Series IV • Volume 10 Volume • • Series IV Clear Wind West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nited States Cryptologic History Series IV: World War II Volume X West Wind Clear: Cryptology and the Winds Message Controversy - A Documentary History Robert J. Hanyok and David P. Mowry Center for Cryptologic History National Security Agency 2008 Table of Contents Preface and Acknowledgments . vii Foreword. .. xxi Chapter 1: Background: Interwar U.S. - Japan Relations and Cryptology. 1 United States-Japan Relations, 1919-1940 (Japanese Diplomatic and Naval Cryptology and American Codebreaking between the Wars) United States - Japan Relations Worsen, 1940-1941 Chapter 2: Intercepted Japanese Diplomatic Messages Reveal a Warning System, 19 November-28 November 1941. .15 The Cryptography of the J-19 System Japan Fields a New Diplomatic Manual Cryptographic System The Americans Solve the New Manual System November 19: Japanese Message #2353 – The First Winds Instruction Message November 19: Japanese Message #2354 – The Second Winds Instruction Message Chapter 3: The Hunt for the Winds Execute Message, 28 November – 7 December 1941 . .. 31 The Search Begins – 28 November 1941 Tokyo Sends More Instructions about Destroying Cryptographic Material The Hidden Word Message – A Complement to the Winds Messages Tokyo Sends Even More Instructions, 28 November-6 December 7 December 1941: The Hidden Word Message Is Sent 7 December 1941: The Winds Execute Message Is Sent Chapter 4: The Winds Controversy: Myth and Reality. .53 Captain Laurance Safford – In the Eye of the Controversy Safford Searches for the Missing Winds Execute Message Safford’s Detailed Claim about the Winds Execute Message – February 1946 Examining Safford's Version(s) of Events The Intercept of the Winds Execute Message Page iii Actions Taken in the Aftermath of the Winds Execute Message Who Saw the Winds Execute Intercept or Translation? The Matter of Missing or Destroyed Records Some Observations on Captain Laurance Safford The Case of Captain Alwin Kramer’s Changing Testimony What the Japanese Said about the Winds Execute Message What the British and Dutch Radio Monitors Heard The Winds Controversy Resurfaces – Ralph Briggs’ Claim The Winds Execute: The Final Casting Afterword: The Winds Message, American Cryptology and History . 95 The Impact and Intelligence Value of the Winds Messages What the Winds Messages Tell Us about Prewar American Cryptology The Winds Messages and the Historical Process Exhibits (Nos. 1 to 55). 103 1. Recovered Decode Chart of Text for J-19 Transposition System 2. Japanese J-19 Transposition Matrix or Stencil 3. Intercept copy of Japanese Diplomatic Message No. 2353 4. Intercept copy of Japanese Diplomatic Message No. 2354 5. K-10/J-19 Indicator Groups and Transposition Key for November 1941 6. Message No. 2353 translation worksheet 7. Kana texts of Japanese diplomatic messages Nos. 2353 and 2354 8. U.S. Navy translation of message No. 2353 (SIS #25432/JD-1: 6875) 9. Revision of translation of No. 2353 (26 September 1944) 10. True form or matrix (stencil) for message No. 2354 11. Translation worksheet of message No. 2354 12. U.S. Navy translation of message No. 2354 (SIS #25392/JD-1:6850) 13. Revision of translation of message No. 2354 (26 September 1944) 14. Transcription of Morse (Kana) Japanese news broadcast 8 December 1941 15. Message from Commander-in-Chief Asiatic Fleet to Washington re: British intercept of Winds instructions, 28 November 1941 16. Intercepted version of “Stop” message No. 2409 27 November 1941 Page iv 17. Stencils of decrypted version of message No. 2409 18. Translation worksheets for message No. 2409 19. Translation of Japanese diplomatic message No. 2409 20. Example of telegram from Japanese Consulate, Honolulu, encrypted in J-19 21. Translation of Japanese diplomatic message No. 118, 28 November 1941 22. FCC documents related to monitoring Japanese broadcasts, 18 August 1944 23.FCC translation worksheets for Japanese “weather” broadcasts on 4, 5, and 8 December 1941 24. FCC, Radio Intelligence Division logs, 28 November - 8 December 1941 25. Translation of Japanese diplomatic message No. 2444, 1 December 1941 26. Translations of Japanese diplomatic message Nos. 2445 and 2447, 2 December 1941 27. Translation of Japanese diplomatic message No. 867, 2 December 1941 28. Translation of Japanese diplomatic message No. 2461, 3 December 1941 29. Listing of HARUNA messages from Japanese diplomatic facilities 30. WDGS G-2 message to Hawaii Department regarding contact with Commander Joseph Rochefort, 5 December 1941 31. Translation of 8 December 1941 Broadcast with Winds message - “West Wind Clear” 32. Intercepted “hidden word” or “Stop” message No. 2494, 7 December 1941 33. Corrected translation of 7 December 1941 “hidden- word” message 34. War Department message to monitoring stations requesting copies of all Japanese clear messages with “Stop” 35. U.S. Navy Technical Mission to Japan interrogation No. 11 – Mr. Shinroku Tanomogi, 30 November 1945 36. U.S. State Department message to London, United Kingdom, Canberra, Australia, and The Hague, Netherlands, requesting information on monitoring for Japanese Winds message, 6 November 1945 37. Message from American legation, Canberra, Australia, 16 November 1945 38. Messages from American embassy, The Hague, Netherlands, 5, 6 December 1945 and 26 January 1946 39. Messages from American embassy, London, United Kingdom, Page v 4, 15 December 1945 and 31 January 1946 40. Captain Laurance Safford’s statement before the Joint Congressional Committee, 25 January 1946 41. Letter from Captain Safford to Commander Alwin Kramer, 22 December 1943 42. Letter in response, Kramer to Safford, 28 December 1943 43. Safford’s coded letter to Kramer, 22 January 1944 (with code listing) 44. Letter, Admiral Husband Kimmel to Admiral William Halsey, 18 March 1944 45. Memorandum, Subject: “JD-7001, Special Studies Covering.” 8 November 1945 46. Morio Tateno interview, 30 June 1961 47. Memorandum to Carter W. Clarke from William F. Friedman, plus handwritten notes, 19 September 194. 48. Operator log for Station “M,” 2 December 1941, with notation by Ralph Briggs 49. Message describing destruction of Cheltenham facility records, 3 November 1945 50. Operator log for Station “M” without notation by Ralph Briggs 51. Message from COIS, Singapore, received in London 8 December 1941 52. Cable from S.I.S. representative in Manila to S.I.S. representative in Honolulu, 3 December 1941 53. British response (GC&CS #11279), 31 August 1945 to Colonel Clausen inquiry 54. Multinational Diplomatic Translation #25783 55. Telegram from Walter Foote, U.S. Consulate General 56. True form or matrix (stencil) for message No. 2353 Glossary of Terms and Abbreviations. 317 Sources and Selected Bibliography. .319 Index. .323 Page vi Preface and Acknowledgments “There is nothing makes a man suspect much, Short, both claimed in later statements during their More than to know a little.” – Francis Bacon testimony before the Joint Congressional Committee reviewing the attack that if they had had In the seemingly never-ending debate over the 7 knowledge of the Winds message they could have December 1941 Japanese attack on Pearl Harbor, prepared for an attack.1 To some adherents of this one of the significant topics of contention pressed claim, the Winds message had acquired a near by some revisionist and conspiracy writers, histori- mythic status within the larger controversy over ans, and critics of the conventional view of the Pearl Harbor.2 attack and the Roosevelt administration’s role in it has been the phenomenon of the so-called “Winds During and after the war, the Japanese surprise Message” (hereafter referred to as Winds message). attack on Pearl Harbor was subjected to a number In the years after World War II, several writers and of investigations by the United States government. scholars and a few politicians espoused the position In fact, the attack was the subject of eight separate that this message was a clear warning that the investigations from late 1941 through mid-1946. Japanese were going to attack the U.S. fleet at Pearl Among them, three were conducted by the Navy Harbor. They have also argued that, beyond the Department, three by the War Department, and simple fact of the occurrence of the Winds message, one was chaired by Associate Supreme Court the contents and importance of this message had Justice Owen Roberts that began within weeks of been revealed to senior American civilian and mili- the attack. The final and most comprehensive was tary leaders. They have contended further that the the postwar hearings by the Joint Congressional failure by Washington to warn the army and naval Committee under the chairmanship of Senator commands at Pearl Harbor, even though the for- Alben Barkley (D-KY), which, among other things, mer had intercepted the warning, made the ensuing incorporated all of the evidence, testimony, calamitous attack inevitable. After the attack,