wrote an op-ed for the Guardian:

"In my estimation, there has not been in American history a more important leak than Edward Snowden's release of NSA material – and that definitely includes the Pentagon Papers 40 years ago."

Ellsberg told CNN he'd been waiting "decades" for someone like Snowden to emerge. "Decades in a sense that of seeing somebody who really was prepared to risk his life for his country as a civilian," he said. "To show the kind of courage that we expect of people on the battlefield."

And while Daniel Ellsberg is a highly regarded public figure these days, it remains to be seen how Snowden will be viewed. A BuzzFeed analysis on Sunday found that those calling him a "hero" outnumbered those calling him a "traitor" by 30 to 1 on Twitter.

More than 17,000 people have signed a petition urging President Obama to pardon the man who revealed details about two classified NSA programs.

The “Pardon Edward Snowden” petition created on Sunday calls the former NSA employee and government contractor a "a national hero" who deserves a full pardon. The petition on the official White House website had more than 17,000 signatures as of 12:45 p.m. Monday.

"Edward Snowden is a national hero and should be immediately issued a a full, free, and absolute pardon for any crimes he has committed or may have committed related to blowing the whistle on secret NSA surveillance programs,"
the petition states.

Snowden, a 29-year-old former CIA employee and government contractor, revealed himself Sunday as the source of stories from The Guardian and The Washington Post about the NSA’s classified surveillance activities.