When the president says these leaks "shed more heat than light", he's been not being specific.
If a single person had died as a result of Snowden's actions, the US Government would trumpet the loss as the most tragic breach of national security and call Snowden a murderer.
Why on earth would the US reveal to the world that Snowden's actions have hurt the country, or an American in some way? Not the sort of thing you announce to your potential adversaries if you want to be taken seriously or be feared in any way. It's also the same reason why we don't hear of the effectiveness of the NSA's spying efforts, it's just something they're not going to ever publicly talk about as it relates directly to national security.
Two weeks after Edward Snowden's first revelations about sweeping government surveillance, President Obama shot back. "We know of at least 50 threats that have been averted because of this information not just in the United States, but, in some cases, threats here in Germany," Obama said during a visit to Berlin in June. "So lives have been saved."
In the months since, intelligence officials, media outlets, and members of Congress from both parties all repeated versions of the claim that NSA surveillance has stopped more than 50 terrorist attacks. The figure has become a key talking point in the debate around the spying programs.
Fifty-four times this and the other program stopped and thwarted terrorist attacks both here and in Europe — saving real lives," Rep. Mike Rogers, a Michigan Republican who chairs the House Intelligence Committee, said on the House floor in July, referring to programs authorized by a pair of post-9/11 laws. "This isn't a game. This is real."
...
Earlier this month, Sen. Patrick Leahy, D-Vt., pressed Alexander on the issue at a Senate Judiciary Committee hearing.
"Would you agree that the 54 cases that keep getting cited by the administration were not all plots, and of the 54, only 13 had some nexus to the U.S.?" Leahy said at the hearing. "Would you agree with that, yes or no?"
"Yes," Alexander replied, without elaborating.
I believe this has subsequently been revised to zero...
If a single person had died as a result of Snowden's actions, the US Government would trumpet the loss as the most tragic breach of national security and call Snowden a murderer.
But they haven't. Because they can't.