"Is it just me, or is secret blanket surveillance obscenely outrageous?" wrote Gore, the Democrat who lost the 2000 presidential election to George W. Bush.
But Sen. Lindsey Graham, R-S.C., said he had no problem with the court order and the practice, declaring, "If we don't do it, we're crazy."
"If you're not getting a call from a terrorist organization, you've got nothing to worry about," he said.
Arizona Sen. John McCain, who ran against Obama for president in 2008, said that if the records sweep was designed to track "people in the United States who are communicating with members of jihadist terrorist organizations," that might not be a problem. "But if it was something where we just blanket started finding out who everybody called and under what circumstances, then I think it deserves congressional hearings."
Senate Democratic leader Reid played down the significance of the revelation.
"Right now I think that everyone should just calm down and understand that this isn't anything that's brand new," he said. "This is a program that's been in effect for seven years, as I recall. It's a program that has worked to prevent not all terrorism but certainly the vast, vast majority. Now is the program perfect? Of course not."
The disclosure of the records sweep was just the latest controversy to hit the Obama administration.
The president also is facing questions over the Internal Revenue Service's improper targeting of conservative groups, the seizure of journalist phone records in an investigation into who leaked information to the media, and the administration's handling of the terrorist attack in Libya that left four Americans dead.
At the very least, the controversies threaten to distract the White House at a pivotal time, when the president wants to tackle big issues like immigration reform and taxes. At most, the controversies collectively could erode the American people's trust in him, threatening both to derail his second term agenda and sully his presidential legacy.
The court order did not authorize snooping into the content of phone calls. But with millions of phone records in hand, the NSA's computers can analyze them for patterns, spot unusual behavior and identify what are known in intelligence circles as "communities of interest" — networks of people in contact with targets or suspicious phone numbers overseas.
Once the government has zeroed in on numbers it believes are tied to terrorism or foreign governments, it can go back to the court with a wiretap request. That allows the government to monitor the calls in real time, record them and store them indefinitely.
The court document related to Verizon offers a glimpse into the larger NSA effort. Under the law, the government would need to demand records from each phone company individually. While subpoenas for other phone companies have not been made public, for the data-mining program described by government officials to work, the government would need records for all providers.
"There is no indication that this order to Verizon was unique or novel. It is very likely that business records orders like this exist for every major American telecommunication company, meaning that if you make calls in the United States the NSA has those records. And this has been going on for at least 7 years, and probably longer," wrote Cindy Cohn, general counsel of the nonprofit digital rights group Electronic Frontier Foundation, and staff attorney Mark Rumold, in a blog post.
Jim Harper, a communications and privacy expert at the libertarian-leaning Cato Institute, questioned the effectiveness of using so-called pattern analyses to intercept terrorism. He said that kind of analysis — finding trends in transactional data collected by Verizon — would produce many false positives and give the government access to intricate data about people's calling habits.
"This is not just entertainment or a sideshow. This is a record of who you called every day this month," he said, urging Congress to require the government to provide "a full explanation" of how this data turns up terrorism plots.
- Debate Takeaways: Rubio shaken, Trump not...
- Rubio faces barrage of attacks in Republican...
- Over 100 missing, 14 dead as strong quake...
- Charity parodies — videos tell another...
- 5 things to know about the Super Bowl and sex...
- N. Korea praises launch, others see as covert...
- Pope's sex abuse panel tells survivor to take...
- Police think 6 Chicago deaths result of...
- US adds just 151k jobs in January; 4.9... 29
- Donald Trump calls for Iowa election... 14
- Kentucky Sen. Rand Paul quits 2016 GOP... 12
- Once a bromance, now a brawl: Trump and... 10
- 5 things to know about the Super Bowl... 9
- In a U.S. divided on gun control,... 8
- Clinton's New Hampshire challenge:... 6
- Clinton wins Iowa, campaigns turn to... 5