Terrorist change their methods of communication after Snowden betrayal

Reuters:

Terrorists have substantially changed their methods of communication since leaks by former U.S. intelligence operative Edward Snowden, hindering intelligence agencies' efforts to track them, a senior British security official said on Tuesday.

"The Snowden effect has been a very, very severe one," Stephen Phipson, a director at Britain's Office for Security and Counter Terrorism (OSCT), told a London security conference.

Snowden, a former National Security Agency (NSA) contractor, caused international uproar last June when he disclosed details of the extent of surveillance and electronic intelligence gathering by his former employers and by the British equivalent GCHQ to the Washington Post and Britain's Guardian newspaper.

"Our adversaries, the terrorists out there, now have full sight of the sorts of tools and range of techniques that are being used by government," he said. "I can tell you data shows a substantial reduction in the use of those methods of communication as a result of the Snowden leaks."
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We will have more difficulty thwarting their planned attacks because they have changed their methods of communication.  We missed the 9-11 attacks because we disclosed at the trial of the African embassy bombers that we were intercepting bin Laden's satellite phone conversations.  These kinds of intelligence breaches can be costly in human casualties.