'THE HIGHEST HONOR'
"Being called a traitor by Dick Cheney is the highest honor you can give an American, and the more panicked talk we hear from people like him ... the better off we all are," Snowden said. Cheney was instrumental in the expansion of surveillance programs after the September 11, 2001, terrorist attacks.
Snowden said he had not had any contact with the Chinese government, and he took care not to reveal any US operations against military targets.
"I pointed out where the NSA has hacked civilian infrastructure such as universities, hospitals and private businesses because it is dangerous," he said.
Snowden answered about 18 questions on the Guardian's website during the session, which lasted more than 90 minutes and drew more than 2,000 comments and questions.
He said he was disappointed that many of Obama's campaign promises had not been realized.
"He closed the door on investigating systemic violations of law, deepened and expanded several abusive programs, and refused to spend the political capital to end the kind of human rights violations like we see in Guantanamo, where men still sit without charge," Snowden said.
He also called on Obama to appoint a special committee to review the surveillance programs.
"This disclosure provides Obama an opportunity to appeal for a return to sanity, constitutional policy, and the rule of law rather than men," he said.
"He still has plenty of time to go down in history as the President who looked into the abyss and stepped back, rather than leaping forward into it."
Snowden said he was encouraged by the public debate over privacy rights and the limits of government that sprung up in the aftermath of the disclosures.
But now, he said, the media was more concerned with "what I said when I was 17 or what my girlfriend looks like rather than, say, the largest program of suspicionless surveillance in human history."
Snowden's father, Lonnie, said in an interview on Fox News that he hoped his son would return to the United States to fight any potential criminal charges.
"I would like to see Ed come home and face this. I shared that with the government when I spoke with them. I love my son," he told Fox, adding "I hope, I pray" that he does not commit any acts that could be considered treason.
"I sense that you're under much stress (from) what I've read recently, and (ask) that you not succumb to that stress ... and make a bad decision," Lonnie Snowden said in an interview published on the channel's website.
He denied press reports that his son was a high school dropout, saying that after a lengthy illness at the start of his sophomore year, his son enrolled in community college and eventually got a high school equivalency degree.
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US surveillance program exposed