A deal for Snowden?

The NSA officer in charge of assessing the damage done by the Edward Snowden leaks says that, under the right conditions, he would consider a deal with the fugitive in return for the documents he has not leaked yet. But the Army general who heads the NSA says he would not consider any deal for Snowden, who's been charged with espionage for stealing maybe the most potentially damaging trove of national secrets in U.S. history.  The NSA granted the rare interviews and allowed 60 Minutes cameras into the agency's secure Maryland complex to explain what it does and what it says it doesn't do -- spy on Americans, a misconception it says the leaks have created.  During the course of the report, the agency also reveals it discovered a secret computer weapon and discusses it for the first time with John Miller for the report, to be broadcast on 60 Minutes Sunday, Dec. 15 at 7 p.m. ET/PT.

Snowden has been given asylum in Russia. The former contractor for the NSA is said to have stolen 1.7 million classified documents. "I wouldn't dispute that [figure]," says Rick Ledgett, the NSA officer who heads the task force investigating the leak and subsequent damage. So far, Snowden has leaked thousands of documents, revealing more embarrassing than damaging information.  He has said he would come back if granted amnesty. Miller asks Ledgett if he would make a deal. "My personal view is, yes, it's worth having a conversation about," he says, but only if he were absolutely assured the remaining documents are secured. "My bar for those assurances would be very high," he tells Miller, "...more than just an assertion on his part."

It's a view Ledgett says others at the NSA share, but not everyone agrees with, including his boss.  "This is analogous to a hostage taker taking 50 people hostage, shooting 10 and then say 'You give me full amnesty and I'll let the other 40 go,'" says Gen. Keith Alexander, the Army officer in charge of the NSA.   The general believes Snowden should be held accountable and a deal would only set a dangerous precedent for anyone else who would abscond with classified information.

Gen. Alexander says that he offered his resignation in the face of this leak, but says his superiors rejected his offer, telling him it could have happened to anyone in the intelligence community.

Miller also speaks to NSA Information Assurance Director Debora Plunkett, who reveals the discovery by one of her 3,000 analysts of a secret computer weapon that could destroy any computer it infected.  She would not name its origin, but 60 Minutes has learned it was engineered in China. The NSA allowed Plunkett to talk about it for the first time in detail.  She says it was called the Bios Plot, for the foundational component, the Bios, that all computers have that performs basic functions like turning on the operating system and activating the hardware. The attack on the Bios would have been disguised as a request for a software update. If the user clicked on it, the virus would turn their computer into "a brick," says Plunkett.

"One of our analysts actually saw that the nation-state had the intention to develop and deliver, to actually use this capability to destroy computers," Plunkett says.  If successful, says Plunket, "Think about the impact of that across the entire globe. It could literally take down the U.S. economy," she tells Miller. The NSA quietly worked with computer manufacturers to eliminate this vulnerability.