Absolutely. The most famous American case is that of Daniel Ellsberg, who in 1971 was nicknamed The Most Dangerous Man in America after he leaked 7,000 pages of top-secret documents about the Vietnam War to the New York Times. Ellsberg, who worked for the RAND Corporation (Snowden worked for a contractor as well), secretly photocopied a 47-volume report that revealed that the U.S. government had lied about the prosecution of the Vietnam War.

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