Snowden told The Washington Post in an interview published online Monday night that he was satisfied because journalists have been able to tell the story of the government's collection of bulk Internet and phone records, an activity that has grown dramatically in the decade since the Sept. 11, 2001, terrorist attacks.
"For me, in terms of personal satisfaction, the mission's already accomplished," he said. "I already won."
"As soon as the journalists were able to work, everything that I had been trying to do was validated," Snowden told the Post. "Because, remember, I didn't want to change society. I wanted to give society a chance to determine if it should change itself."
President Barack Obama hinted Friday that he would consider some changes to NSA's bulk collection of Americans' phone records to address the public's concern about privacy. His comments came in a week in which a federal judge declared the NSA's collection program probably was unconstitutional. A presidential advisory panel has suggested 46 changes to NSA operations.
Snowden was interviewed in Moscow over two days by Post reporter Barton Gellman, who has received numerous leaks from Snowden. The interview was conducted six months after Snowden's revelations first appeared in the Post and Britain's Guardian newspaper.
Gellman described Snowden as relaxed and animated over two days of nearly unbroken conversation, fueled by burgers, pasta, ice cream and Russian pastry.
In June, the Justice Department unsealed a criminal complaint charging Snowden, a former NSA contractor, with espionage and felony theft of government property. Russia granted him temporary asylum five months ago.
The effects of Snowden's revelations have been evident in the courts, Congress, Silicon Valley and capitals around the world, where even U.S. allies have reacted angrily to reports of U.S. monitoring of their leaders' cellphone calls. Brazil and members of the European Union are considering ways to better protect their data and U.S. technology companies such as Google, Microsoft and Yahoo are looking at ways to block the collection of data by the government.
Snowden, now 30, said he is not being disloyal to the U.S. or to his former employer.
"I am not trying to bring down the NSA, I am working to improve the NSA," he said. "I am still working for the NSA right now. They are the only ones who don't realize it."
Asked about the Snowden interview, White House spokeswoman Caitlin Hayden said: "Mr. Snowden faces felony charges here in the United States and should be returned to the U.S. as soon as possible, where he will be afforded due process and all the protections of our criminal justice system."