Formerly-Secret NSA Document Rewrites Vietnam War History

Did the NSA lose a treasure trove of top-secret cryptographic equipment and material to the North at the end of the Vietnam war? Investigative journalist and NSA expert James Bamford has said so. But in 2002, official NSA historians refuted that in an internal essay. Of course, this being NSA, the rebuttal was classified.

Now that essay, SIGINT and the Fall of Saigon, April 1975, has been (mostly) declassified in a Mandatory Declassification Review initiated by attorney and journalist Michael Ravnitzky. Here's the NSA's side of the story, formerly classified Secret, meaning disclosure would cause serious harm to U.S. national security.

Regarding the destruction of COMSEC and cryptological material and equipment, certain writers, such as James Bamford in Body of Secrets, have claimed that this loss constituted a major compromise. This simply was not true. All current or sensitive equipment had been removed or destroyed by the Americans and South Vietnamese. However, a large amount of material, mostly South Vietnamese codes, ciphers, and keying material was lost. Also, a substantial amount of crypto-equipment, such as M-209 cipher devices and tactical secure speech gear such as the KY-8 (Nestor), was lost. However, an NSA survey correctly assessed the potential for compromise as negligible as a result of these losses. The South Vietnamese crypto-material had no cryptographic relationship to the U.S. systems. As for the equipment, it was either vintage, and no longer used by the United States, as in the case of the M-209, or, like the tactical secure speech equipment, many sets had already been lost during the war.

Here's Bamford's account, from the excellent Body of Secrets (2001).

Within a few hours, Saigon had been taken over and renamed Ho Chi Minh City. But while the departing embassy employees left only ashes and smashed crypto equipment for the incoming Communists, NSA had left the NVA a prize beyond their wildest dreams. According to NSA documents obtained for Body of Secrets, among the booty discovered by the North Vietnamese was an entire warehouse overflowing with NSA's most important cryptographic machines and other supersensitive code and cipher material, all in pristine condition -- and all no doubt shared with the Russians and possibly also the Chinese. Still not admitted by the NSA, this was the largest compromise of highly secret coding equipment and materials in U.S. history.

Which version is correct? We could let history decide. But I suggest a secret-paperwork showdown: Bamford should release the classified documents he mentions and pit them against NSA's declassified history. THREAT LEVEL will referee.

The Vietnam essay was one of four newly-declassified documents NSA prepared for its 50th anniversary Cryptologic Almanac. Here are the PDFs, courtesy of the Federation of American Scientists:

Quis Custodiet Ipsos Custodes? (.pdf) on the origins of NSA.

SIGINT and the Fall of Saigon, April 1975 (.pdf)

The First Round: NSA's Effort Against International Terrorism in the 1970s (.pdf)

A Brief Look at ELINT at NSA (.pdf)

(photo: Hubert Van Es)