Data Mining: What Does The NSA Collect About Americans?

This past weekend at Defcon, the nation's largest convention of computer hackers, National Security Agency Chief Gen. Keith Alexander insisted that his agency doesn't keep files on ordinary Americans.

In response, former NSA official William Binney responded that in fact the agency does collect data, and it's even indexed, and that's why he left the agency.

So what's true, and what's most beneficial? After the Colorado shooting people asked why law enforcement wasn't mining data on shooter James Holmes, who bought huge amounts of ammunition online and tried to join a gun club. And last week on Here & Now, we heard national security expert James Bamford say if Holmes had a Muslim name, he would have been data mined.

So, where are we on data mining, nearly ten years after the Pentagon's controversial Total Information Awareness data mining program was killed by Congress out of concern it violated civil liberties?

James Bamford says that in the past decade the National Security Agency has transformed itself into the "largest, most covert, and potentially most intrusive intelligence agency ever created," and it has "turned its surveillance apparatus on the U.S. and its citizens" for the first time since Watergate.

And one of its weapons is a heavily-fortified data mining facility in Utah, expected to be five times the size of the U.S. Capitol, where Americans' e-mails, cellphone calls, Google searches, parking receipts and travel itineraries (what Bamford calls "digital pocket litter") will be stored.