Bret Baier got a behind-the-scenes look at the National Security Operations Center in the second part of an exclusive interview with outgoing NSA Director Gen. Keith Alexander.

Howie Larrabee, NSA National Security Operations Center director, said the center has been staffed every day for 40 years. He said it’s the place where the NSA responds to unfolding world events.

“You can think of us as the emergency room in a hospital, where we triage and assess a situation, and we direct the immediate time-sensitive response of that cryptologic enterprise,” Larrabee said.

Alexander gets his briefings there. He said it’s where the NSA learns a lot about terrorism and what’s going on with some of the nation’s adversaries. This, he said, is where they “connect the dots, stop the next 9/11.”

Watch the full clip above.

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