In the labyrinthine and opaque history of the United States's relationship with Israel, the deadly 1967 attack by Israeli fighter jets on a United States Navy intelligence ship, the USS Liberty, remains a sore point and is much debated. Despite the sensitivity of the incident -- it involved the most secretive agency in government, a most important American alliance, extremely sensitive technical details, historians and journalists have an enormous reservoir of documents to mine through, and most of the major players have long-since given their first-person interviews.
The official version is that the U.S. accepts the Israeli explanation for the attack; that it was an accident, the result of a chain of errors in judgment, command and execution. But the truth is that it the U.S. government was skeptical for far longer than had been previously acknowledged. (The Chicago Tribune's John Crewdson has perhaps the most comprehensive, most compelling recent account of the controversy.) One of the key disputes: was the ship itself, or another NSA collection technology, monitoring Israeli defense communications? (And did Israel, figuring this out, seek to disable the ship or send a message to Americans by strafing it?)
The official declassified NSA history says no, although there is a caveat; "Although there was no sigint bearing directly on the attack, there was a [16 LETTER REDACTION] report shortly after the incident dealing with the aftermath. It detailed air-ground communications between a controller as Halstor and two Israeli helicopters with reconnoitered the Liberty as it was turning toward Malta."
We are left to guess at what's redacted. Here's a clue: Crewdson's 2007 article notes that a Navy SIGINT collection airplane picked up conversations between the helicopters and Israeli controllers in the immediate aftermath. The Navy specialist who listened to the events in real-time told Crewdson that the NSA's voluminous release of documents was incomplete.
Here's a portion from the new history:
The entire history, which will take us afficiandos a while to pluck through, was once classified as Top Secret Umbra, with Umbra denoting intelligence of a specific level of sensitivity. At the bottom of the document, the reader is instructed to Handle Via Talent-Keyhole Comint Channels Jointly. For those who aren't intel fetishists, Talent-Keyhole is a category designation of sensitive compartmented information that deals with signals intelligence. Talent information deals with aircraft-gathered intelligence; Keyhole denotes imagery (imint) from satellites. Comint refers to sensitive signals intelligence methods and sources. Basically, the history was written at a level of classification that basically forbid even many intelligence professionals from reading it. Of course, that's all been declassified. Or most of it -- the documents are studded with fascinating redactions...
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