Imagine if the government required every American to report to the government every night who they spoke to, or texted, for how long, and from where. People would be furious, but that’s precisely the information the N.S.A. is collecting from telecom companies. And it’s precisely why the government desperately wanted to keep the practice a  secret.  http://takingnote.blogs.nytimes.com/2013/06/07/whats-the-purpose-of-the-n-s-a-surveillance-program/
The White House, desperately trying to defend a huge phone-surveillance program it should have shut down years ago, made an interesting claim on Thursday: Collecting millions of phone records of ordinary citizens allows law enforcement “to discover whether known or suspected terrorists have been in contact” with other possible terrorists. If counter-terrorism officials are following a suspect and want to know his contacts, they can easily get a court order to obtain the details of his specific conversations. For that matter, they can get permission to wiretap him, too.
Investigators might want to keep data longer than a phone or Internet company would, so they can search through years of a suspect’s records, but that’s too slim a purpose by itself to justify a program of this depth. What’s far more likely is that the government is using these records to try to identify terrorists in the first place, not follow them once they are known. Using a high-speed computer, the National Security Agency mines the huge amount of data it gathers daily for patterns that might indicate suspicious activity — calls to a country or a specific person overseas.
What the public never learns is how many of those patterns lead to wiretaps of innocent citizens. The Guardian reported that the Internet-search program, known as PRISM, results in 2,000 further reviews of messages every month, which means that government investigators read the actual contents of tens of thousands of messages. That number undoubtedly includes many false hits on people who were not communicating about terrorist plots.