Nobody knows except the government. It seems plausible that phone call records 鈥 the metadata of Americans鈥 calls 鈥 may be sitting in an NSA database. It鈥檚 possible that social media data posted on the Web are in a NSA database, too. But until Google and others can reveal what kinds of data were given to the government, we won鈥檛 know.

Rick Bowmer/AP
The NSA's Utah Data Center in Bluffdale, Utah., is filled with super-powered computers designed to store massive amounts of information gathered secretly from phone calls and e-mails.