WASHINGTON -- The head of the National Security Agency, Gen. Keith Alexander, defended his agency's surveillance of millions of Americans' Internet and phone records, telling a Senate committee Wednesday that the programs were critical in disrupting dozens of terror attacks in the United States and abroad.
"It's dozens of terrorist events that these have helped prevent," Alexander told Sen. Pat Leahy (D-Vt.), adding that those alleged plots have been in the United States and abroad.
Revelations that the NSA has been collecting records of phone calls in the United States and sweeping up vast amounts of Internet data have sparked a furor in Congress, with lawmakers sharply divided on whether the actions are appropriate. At specific issue are Section 215 of the Patriot Act and Section 702 of the Foreign Intelligence Surveillance Act. The first authorizes the gathering of "business records," such as phone numbers, and the second allows vast data mining.
Pushed by Leahy -- who wants to put expiration dates on such laws -- Alexander elaborated on the case of Najibullah Zazi, who plotted to bomb the New York City subway system.
Alexander argued that not only was information sourced from overseas web communications vital in foiling Zazi's plot, such data "developed the lead on it. I would say it was the one that allowed us to know it was happening."
He added that once the cyber sweeps had picked up the Zazi plot, the NSA was able to go to the FBI, which identified who Zazi was communicating with using phone records.
"These authorities complement each other," Alexander said. "We've got to help make that clear to you."
The spy agency boss also pledged to make public exactly how many terror plots the two surveillance operations have uncovered.
Sen. Dianne Feinstein (D-Calif.), a backer of the programs, spelled out one detail that may have escaped the notice of many members of the public: The NSA sweeps up records of all phone calls and holds them for five years. Alexander confirmed that she was correct.
In spite of Alexander's assertions, some senators still suggested that the programs are too broad and could be narrowed to be less intrusive on Americans' civil liberties.
Sen. Jeff Merkley, who who is pushing legislation to make the NSA more transparent, demanded to know how the laws could be read to justify the NSA keeping such a massive trove of data, including on the senator's own phone, which he held up as a prop.
"The standard for collecting phone records on Americans is now all phone records, all the time, all across America," Merkley said, noting that Section 215 requires applications for collecting data to have a statement of facts showing reasonable grounds that the "tangible things" sought are relevant to an authorized investigation.
"Here I have my Verizon phone, my cell phone. What authorized investigation gave you the grounds for acquiring my cellphone data?" Merkley asked.
Watch Merkely below:
Alexander did not answer, but he pledged to try and do so after hashing the matter out in a closed hearing before the intelligence committee set for Thursday.
"I do think that should be answered," he said, and went on to offer a justification for why he thought the government's reasoning should be made public.
"I think what we're doing to protect American citizens here is the right thing," Alexander said. "Our agency takes great pride in protecting this nation and our civil liberties and privacy, and doing it in partnership with this committee, with this Congress and with the courts. We have everybody there. We aren't trying to hide it. We're trying to protect America."
Sen. Tom Udall (D-N.M.), who voted agaisnt the legislation that allows the NSA's activities, extracted a promise from Alexander to cooperate with an investigation.
"It's very difficult, I think to have a transparent debate about secret programs, approved by a secret court issuing secret court orders based on secretive interpretations of the law," Udall said.
Sen. Jon Tester (D-Mont.) also suggested that maybe the system itself is flawed, pointing to the self-professed leaker who revealed the programs, Edward Snowden, a 29-year-old who was not even directly employed by the U.S. government.
"Whatever one thinks of Edward Snowden, it looks to me as if we've also got a big problem that is internal, not external," Tester said. "How on earth did this happen? And why does a contractor have access to information that we're spending $13 billion to prevent outsiders from getting their hands on?"
"That's one of the great concerns that we both have," Alexander replied.