Where can I read the Pearl Harbor decrypts?

An article about Pearl Harbor in Sunday's New York Times says 'In the six months before Dec. 7, 239 messages between Tokyo and the Japanese embassy in Washington had been deciphered.' Have these messages been published?

The article goes on to say 'the latest decrypt reaching him one the eve of Pearl Harbor had prompted Roosevelt to conclude 'This means war.'' Has the text of eve this one message been published?

I think that's fairly widely agreed upon. The issue, rather, is whether he had any reason to believe that 'this' meant an attack on Hawaii. I don't believe so, other than the general notion that a military ought to be prepared for the worst eventuality.

all the best

Probably, although I don't know of a good on-line reference. Some references are by people with axes to grind, and who include messages that were deciphered and translated after the war.

This was the first thirteen of the fourteen parts the Japanese ambassador was supposed to deliver to the US Secretary of State half an hour before the Pearl Harbor attack. The document is available at http://www.ibiblio.org/pha/myths/14_part.html and you might well find the other messages you're interested in at the www.ibiblio.orb/pha site.

The fourteenth part of the message actually turned out to be less drastic than Roosevelt had expected, being just a very emphatic breaking off of negotiations rather than a declaration of war, but Roosevelt was correct about the Japanese attacking.

Hi Charles. What they were referring to was PURPLE, the code name given for the diplomatic 'code' (actually a cypher) used by the Japanese. This should not be confused with the Naval system (Called AN before the war and redesignated JN-25 later) which was not 'broken' until Midway, despite what some may say.

The only snippets of PURPLE I know of that exist online are on a page about the PURPLE machine:
http://frode.home.cern.ch/frode/crypto/simula/purple/ index.html

If you want more your best bet is the National Archives at College Park, Maryland.

Some more about PURPLE:

Yes.

Yes.

Title: The 'Magic' background of Pearl Harbor. Publisher: [Washington] : Dept. of Defence, U.S.A. : for sale by the Supt. of Docs., U.S. Govt. Print. Off., [1978] Description: 5 v. in 8 : maps (on lining paper) ; 27 cm.

It contains the cables, including decode dates, the transcripts of bugged Japan-US phone calls and state department assessments of the various meetings.

There is a project at Purdue University to put the above books into electronic form with an index, I am unsure about its current status.

See also

Author: Komatsu, Keiichiro. Title: Origins of the Pacific War and the importance of 'magic'. Publisher: New York : St. Martin's Press, 1999.

Where as part of the work the author looks at the problems with translating Japanese into English and what sort of effects mistranslations had.

Geoffrey Sinclair Remove the nb for email.

Well, here's the biggie:
http://www.ibiblio.org/pha/myths/14_part.html