NSA divided over possible amnesty deal for Snowden

Officials at the National Security Agency are divided over whether to offer an amnesty deal to espionage suspect Edward Snowden, who is said to have cost the agency tens of millions of dollars to ensure his presence was removed from its networks.

The former NSA contractor, who has been granted asylum in Russia, is said to have stolen 1.7 million classified documents from government computers before fleeing the US in June. However, law enforcement officials concede they may never know the size of his haul.

"They've spent hundreds and hundreds of man-hours trying to reconstruct everything he has gotten, and they still don't know all of what he took," a senior administration official told The New York Times. "I know that seems crazy, but everything with this is crazy."

Whether return of that cache is worth a deal with Snowden is a contentious subject within the NSA. Rick Ledgett, who runs the NSA task force assessing the damage on the Snowden leaks, told CBS' news program "60 Minutes" during a segment aired Sunday (see below) that an amnesty deal is "worth having a conversation about. I would need assurances that the remainder of the data could be secured, and my bar for those assurances would be very high. It would be more than just an assertion on his part." (Disclosure: CBS is the parent company of CNET.)

Ledgett concedes that opinion is "not unanimous" within the agency. NSA chief Gen. Keith Alexander compares the amnesty suggestion to a hostage-taker asking for amnesty after killing 10 of 50 hostages.

"I think people have to be held accountable for their actions," Alexander said.

Alexander, who has served as director of the NSA since 2005 and is expected to step down next year, said he offered his resignation as a result of the leak.

"I offered to resign," Alexander said. "And they said, 'We don't see a reason that you should resign. We haven't found anybody there doing anything wrong.'"

During the task force's damage assessment, the NSA discovered Snowden has some unusual habits, especially when working at home.

"He would work on the computer with a hood that covered the computer screen and covered his head and shoulders, so that he could work and his girlfriend couldn't see what he was doing," Ledgett said.

One of the task force's fears was that Snowden might have left a bug or virus behind on the NSA's network. So the agency removed all the computers he had access to on the agency's classified and unclassified networks -- including the cables that connected them -- at a cost Ledgett estimated in the tens of millions of dollars.

While the NSA has come under considerable scrutiny and criticism in the wake of Snowden's leaks, Alexander said the agency's surveillance activities are necessary to the nation's defense. In addition to tracking terrorist activities, the NSA has a team monitoring the threat of cyberattack on the nation's critical infrastructure, including the financial system.

"I believe that a foreign nation could impact and destroy major portions of our financial system," Alexander said.

One threat highlighted during the "60 Minutes" visit was dubbed the BIOS Plot, a virus that would attack the firmware that activates the hardware and operating system. Debora Plunkett, who directs cyber defense for the NSA, warns that such an attack would effectively brick computers.

"Think about the impact of that across the entire globe," Plunkett said. "It could literally take down the U.S. economy."

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