"This is the most serious hemorrhaging of American secrets in the history of American espionage," Hayden said on CBS's "Face the Nation." “What Snowden is revealing … is the plumbing. He’s revealing how we acquire this information.”
"It will take years, if not decades, for us to return to the position that we had prior to his disclosure," he added.
"What I'm most afraid of is that we will reveal our sources and methods, our tactics, techniques and procedures to people around the world who will the American nation and the American people harm."
"I used to say he was a defector ... I'm now kind of drifting in the direction of perhaps more harsh language ... such as traitor," Hayden said.
Hayden also said a report in The New York Times that found no clear linkage between al Qaeda central command and the deadly attack on the diplomatic facility in Benghazi, Libya, had "a ring of truth.”
"When the attack happened, actually on this network a few days afterwards, I was asked who did it," he said. "And I said, 'Well, you know, the Al Qaeda movement divided into three layers, Al Qaeda prime, formerly affiliated and like minded.' And at the time, I said this was probably high-end, like minded or low-end affiliated. And I think the Times story today kind of bears that out.
— This report was updated at 11:51 a.m.