In Georgia, an NSA official said in interviews, the agency had combed through huge volumes of routine e-mails to and from Americans.
And in San Francisco, a technician at AT&T reported on the existence of a secret room reserved for the NSA that allowed the spy agency to copy and store millions of domestic and international telephone calls routed through that station.
Nothing revealed in recent days suggests that NSA eavesdroppers have violated the law by targeting ordinary Americans. On Friday, US President Barack Obama defended the agency’s collection of telephone records and other metadata, saying it did not involve listening to conversations or reading the content of e-mails.
“Some of the hype we’ve been hearing over the past day or so — nobody has listened to the content of people’s phone calls,” Obama said.
Still, some privacy advocates say that the language used by top government officials to describe the NSA’s activities masks the full extent of its operations.
Officials say that the agency does not purposefully “collect” the private data of US citizens unless they are suspected of terrorist activity.
However, the NSA considers “collection” to refer only to the data that agency employees actually analyze and read. The agency acquires huge amounts of US data each day, and then applies what they call “minimization” procedures to protect the information from being used in its analysis. The agency still retains the private data, and the procedures used to block access to it are of its own making.
Privacy advocates say that a national debate must take place to come up with new rules to limit the intelligence community’s access to the mountains of data.
“It is a bit of a fantasy to think that the government can seize so much information without implicating the Fourth Amendment interests of American citizens,” Rotenberg said, referring to the constitutional limits on search and seizure.