The National Security Agency has built a surveillance system - TopicsExpress

The National Security Agency has built a surveillance system capable of recording “100 percent” of a foreign country’s telephone calls, enabling the agency to rewind and review conversations as long as a month after they take place, according to people with direct knowledge of the effort and documents supplied by former contractor Edward Snowden. A senior manager for the program compares it to a time machine — one that can replay the voices from any call without requiring that a person be identified in advance for surveillance. The voice interception program, called MYSTIC, began in 2009.