Gavin writes:

> As far as I know, Navajo was never used for written cryptography as it
>  wouldn't be that hard to break (you would quickly learn which was the
>  picturesque Native American word for "aircraft carrier" and so on).

With the exception of the above paragraph, all of what Gavin writes is quite
true. However, the Navajo never had a written language, idiographic or
otherwise. No North American Indian tribe spontaneously developed any sort of
written language. The only exception to that statement is Chief Sequoya (the
spelling is variable), who learned to speak five languages fluently, including
English and French, who developed a written language for the Cherokee, using
the Latin characters. The petrogylphs common to New Mexico are much older than
the Navajo, who along with the Apache, are very recent immigrants into the
area.

Petrogylphs, on the other hand, are nearly a universal human language, tens of
thousands of years old, and found in every part of the habitable earth.
Moreover, the symbols are surprisingly similiar, adding to the argument that
language development among humans was very slow and very old.

>  The military did employ "Code Talkers" from the Navajo (and later
>  Choctaw and possibly other) nations who manned the radios
>  during assaults by the U.S. Marines.  This provided real time
>  "encryption" for tactical command and control which would otherwise
>  have taken place "in the clear" (i.e. in English).  Even if you wrote
>  down the intercepted traffic the data would no longer have any value
>  by the time you got some idea of what the message had meant.
>
>  These Native American languages were complex, unusual, and very obscure.
>  "Breaking" these codes would require not only someone who was a fluent
>  speaker of the language, but also one who understood the local tribal
>  slang employed, as the people on either end of the connection typically
>  had grown up together in the same place.
>
>  A quick STFW on "code talkers" reveals some details at:
>
>     http://www.history.navy.mil/faqs/faq61-2.htm

A great many of the Code Talkers are still alive -- and are the stuff of
legend here in New Mexico. They still have occasional get-togethers on the
Navajo Reservation to celebrate their WWII contributions.

Wirt Atmar