For years, top officials of the Bush and Obama administrations dismissed fears about secret government data-mining by reassuring Congress that there were no secret nets trawling for Americans' phone and Internet records.

President Barack Obama (Stephen Lam/Getty Images)

But on Friday, President Barack Obama himself acknowledged the existence of such programs while giving the government's standard rationale to ease fears that Americans' privacy rights are being violated.

Obama told reporters in California that sifting through mountains of data could potentially lead investigators to terrorists.

Obama's comments marked the first time a U.S. president publicly acknowledged the government's electronic sleuthing on U.S. citizens. They came in response to media revelations and published classified documents that detailed the government's secret mass collection of phone and Internet communications.

Obama defends broad phone, Internet spy programs

Obama is urging Americans to "make some choices" in balancing privacy and security.

Obama is defending once-secret surveillance programs that sweep up an estimated 3 billion phone calls a day and amass Internet data from U.S. providers in an attempt to thwart terror attacks.

The president says it will be harder to detect threats against the U.S. now that the two top-secret tools to target terrorists have been so thoroughly publicized.

The National Security Agency has been collecting the phone records of hundreds of millions of Americans each day to learn whether terror suspects have been in contact with people in the U.S.

The NSA also has been gathering all Internet usage from major U.S. Internet providers in hopes of detecting suspicious behavior that begins overseas.

Global netizens worried over US spying

A Verizon store in New York (Spencer Platt/Getty Images)

There's concern and some resignation but not much surprise among global users to media revelations of massive U.S. phone and Internet data collection in the name of security.

Many global netizens say they already have few expectations of online privacy as governments increasingly monitor people's digital lives.

Privacy activists are concerned and are calling on people to take measures to better protect their digital data. But most people eschew encryption and other privacy tools.

Jamie Griffiths, a 26-year-old architect working in London notes that he wouldn't send an email that he "wouldn't want a third party to read."

From Baghdad, to Bogota, Colombia, many say they already carefully censor what they write online and assume governments are spying.

The revelations, though, could hurt U.S. technology companies if Internet users become disillusioned and abandon them in favor of more secure alternatives.

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