House Intelligence Committee Chairman Mike Rogers, R-Mich., with Rep. C.A. Dutch Ruppersberger, D-Md., the ranking member, left, speaks at a press conference about proposed changes to the National Security Agency’s program of sweeping up and storing vast amounts of data on Americans' phone calls, at the Capitol in Washington, Tuesday, March 25, 2014. AP Photo/J. Scott Applewhite

It was only months ago that President Obama, with bipartisan backing from the heads of Congress's Intelligence committees, was insisting that the National Security Agency's mass surveillance program was key to keeping Americans safe from the next major terrorist attack. They were also dismissing privacy concerns, saying the program was perfectly legal and insisting the necessary safeguards were already in place.

But now, Obama's full-speed ahead has turned into a hasty retreat: The president and the NSA's top supporters in Congress are all pushing proposals to end the NSA's bulk collection of phone records. And civil-liberties groups — awash in their newly won clout — are declaring victory. The question is no longer whether to change the program, but how dramatically to overhaul it.

So what changed?

It's not that Obama and his Hill allies suddenly saw the error of their ways and became born-again privacy advocates. Instead, with a critical section of the Patriot Act set to expire next year, they realized they had no choice but to negotiate.

If Congress fails to reauthorize that provision — Section 215 — by June 1, 2015, then the NSA's collection of U.S. records would have to end entirely. And the growing outrage prompted by the Snowden leaks means that the NSA's supporters would almost certainly lose an up-or-down vote on the program.

Rep. Adam Schiff, a Democratic member of the House Intelligence Committee, said that looming sunset is what forced lawmakers to the bargaining table. "I think what has changed is the growing realization that the votes are simply not there for reauthorization," he said in an interview. "I think that more than anything else, that is galvanizing us into action."

Obama and the House Intelligence Committee leaders believe their proposals are now the NSA's best bet to retain some power to mine U.S. phone records for possible terror plots. Senate Intelligence Committee Chairwoman Dianne Feinstein, another leading NSA defender, also indicated she is on board with the changes, saying the president's proposal is a "worthy effort."

And though the Hill's NSA allies are now proposing reforms to the agency, they don't seem particularly excited about it.

At a Capitol Hill press conference Tuesday, Rep. Mike Rogers, the Republican chairman of the House Intelligence Committee, and Rep. Dutch Ruppersberger, the panel's top Democrat, often sounded like they were arguing against their own bill that they were unveiling.

"I passionately believe this program has saved American lives," Rogers said. Ruppersberger said if the program had been in place in 2001, it may have prevented the Sept. 11 attacks.

Rogers rejected a reporter's suggestion that the NSA should have never had control of the massive database of phone records in the first place. "There was no abuse, no illegality, no unconstitutionality," he said.

But the lawmakers acknowledged there is broad "discomfort" with the program as it is currently structured. "We need to do something about bulk collection because of the perception of our constituents," Ruppersberger admitted.

Under their legislation, the vast database of phone records would stay in the hands of the phone companies. The NSA could force the phone companies to turn over particular records, and the Foreign Intelligence Surveillance Court would review the NSA orders after the fact.

Rogers and company much prefer their version to a competing proposal to change the way the government gathers information. That would be the USA Freedom Act, a proposal from Senate Judiciary Committee Chairman Patrick Leahy and Rep. Jim Sensenbrenner that Rogers and his ilk fear would go too far in hamstringing the NSA. The USA Freedom Act would require the NSA to meet a tougher standard for the data searches and would limit other NSA programs, such as Internet surveillance of people overseas.

"In my opinion," Ruppersberger said, "the Sensenbrenner bill makes our country less safe."

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