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From NPR News, this is ALL THINGS CONSIDERED. I'm Audie Cornish. "Irreversible and significant damage to U.S. national security" - those words from Gen. Keith Alexander, director of the NSA. He was describing the result of repeated leaks by former contractor Edward Snowden.
Since then, the agency has been considering whether it has to modify its approach to intelligence-gathering. NPR's Tom Gjelten recently raised that question with NSA leaders.
TOM GJELTEN, BYLINE: The Snowden leaks so upset leaders of the U.S. intelligence community that they felt compelled to launch a massive damage assessment, to find out what effect the disclosures would have on intelligence operations. One official says it's by far the biggest such effort ever undertaken.
At the NSA, the assessment has been led by Richard Ledgett, formerly the director of the agency's Threat Operations Center. He says the big concern is that potential terrorists, whose conversations were subject to NSA surveillance, might change to more secure communication now that details of the surveillance programs have been revealed.
RICHARD LEDGETT: If there's disclosure that, you know, NSA can do this thing or that thing or that thing, then they can take action to close that vulnerability.
GJELTEN: But even if terrorists do change their means of communication because of what they find out about NSA surveillance methods, the intercept program, Ledgett says, might still serve a purpose.
LEDGETT: The question then becomes whether the existence of the program causes their operations to proceed more slowly or more difficult, less chance for real-time command and control.
GJELTEN: For example, when Osama bin Laden learned the NSA was monitoring his satellite phone, he started sending messages by courier instead. The messages could not be intercepted, but the change meant bin Laden's communications after that were slower and more cumbersome.
Ledgett says there is one way the Snowden leaks have clearly affected NSA operations: The damage assessment itself has kept NSA employees from doing their regular intelligence work.
LEDGETT: We've devoted a lot of people to looking at the impact of what we think Snowden took. So it's people off task.
GJELTEN: Off task because NSA people got reassigned from intelligence work to investigative work. NSA resources have also been diverted into beefing up security at the agency to prevent future leaks. The agency is now tagging data with restrictions so that analysts aren't able to access the data unless they have the right training, for example.
Lonny Anderson, the NSA's chief information officer, says the change was already in the works before the Snowden disclosures, but it got speeded up. That move cost money the NSA had not planned on spending.
LONNY ANDERSON: We haven't asked for additional resources. We've just said, we've got to do this. So something gives because we're not getting additional resources. So at this point, what gives for us is mission.
GJELTEN: The NSA mission is intelligence gathering, now in danger of taking a backseat to security reforms, Anderson says.
ANDERSON: We have to make sure that we don't cross a line where we're so busy locking down the networks that we're not busy defending the nation.
GJELTEN: The Snowden episode, then, has forced the NSA to adapt. But Richard Ledgett, the chief leak investigator, says it has not prompted the NSA to rethink its whole surveillance operation - not yet, anyway.
LEDGETT: It hasn't caused any major right or left turns yet, in the path the organization is taking, but those things tend to take longer to resolve.
GJELTEN: So no redesign of the surveillance architecture; nor has there been any rethinking of the propriety of NSA surveillance activities in light of objections raised by privacy advocates. Jameel Jaffer, who directs the Center for Democracy at the American Civil Liberties Union, wishes NSA leaders paid more attention to the criticism of their surveillance operation.
JAMEEL JAFFER: I haven't seen yet any willingness to reconsider the policies themselves. But in my view, that's exactly what should be going on. The NSA should be part of this conversation about how broad government surveillance policies ought to be. And thus far, all I've seen from the NSA is a kind of defensiveness about the programs that have been put in place.
GJELTEN: Jaffer says it's ultimately up to Congress and the White House to consider changes in the NSA's surveillance authority. On that, NSA leaders agree. That's a policy decision, says Richard Ledgett, and we don't make that call.
Tom Gjelten, NPR News, Washington.
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