Daniel Ellsberg, who leaked the Pentagon Papers during the Vietnam War, said Edward Snowden, 29, the whistleblower who exposed a National Security Agency wide-ranging surveillance program, showed "the kind of courage that we expect of people on the battlefield."
Ellsberg said on Twitter "there has not been in American history a more important leak than Snowden's," including his own, during Watergate.
In July 1971, Daniel Ellsberg, a former National Security Council consultant and military analyst changed the course of history when he leaked confidential information about the Vietnam War to a reporter at The New York Times. Those documents later became known as The Pentagon Papers.
Snowden, who has fled to Hong Kong, worked for the NSA as a contractor for Dell and Booz Allen over the last four years.
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Ellsberg told The Daily Beast:
"The information about unconstitutional activity that he [Snowden] put out could only be reversed or stopped if the public knows about it, and there was absolutely no way for them or most members of Congress to learn about it without him putting it out.
He went on to say that he identifies with Snowden, "his choice, his decision, his performance" and that the 29-year-old is clearly aware of the consequences of his actions.
He said it is clear is that Snowden broke the law and faces possible of prosecution.
Ellsberg had this to say on CNN: