But the NSA will catch up eventually, he predicted, because there are only so many ways a terrorist can communicate. "I have every confidence in their ability to regain access."
Terror groups switching to encrypted communication may slow the NSA, but encryption also flags the communication as something the US agency considers worth listening to, according to a new batch of secret and top-secret NSA documents published last week by The Guardian, a British newspaper.
They show that the NSA considers any encrypted communication between a foreigner they are watching and a US-based person as fair game to gather and keep, for as long as it takes to break the code and examine it.
Documents released last week also show measures the NSA takes to gather foreign intelligence overseas, highlighting the possible fallout of the disclosures on more traditional spying. Many foreign diplomats use email systems like Hotmail for their personal correspondence.
Two foreign diplomats reached this week who use US email systems that the NSA monitors overseas say they plan no changes, because both diplomats said they already assumed the US was able to read that type of correspondence.
