At a Senate hearing last week, Gen. Keith Alexander, director of the National Security Agency, said the NSA's mass collection of Americans' phone records via Section 215 of the PATRIOT Act has "helped prevent…dozens of terrorist events…both here and abroad." Later in the same hearing, he retreated from that claim, saying he could not "state unequivocally" that the phone record database "contributed solely" to preventing any particular attack. The equivocation continued at yesterday's House Intelligene Committee hearing, where Alexander paired the phone record database with monitoring of foreign targets' communications under Section 702 of the Foreign Intelligence Surveillance Act:

In recent years, the information gathered from these programs provided the U.S. government with critical leads to help prevent over 50 potential terrorist events in more than 20 countries around the world. FAA [FISA Amendments Act] 702 contributed in over 90 percent of these cases. At least 10 of these events included homeland-based threats. In the vast majority, business records, FISA reporting contributed as well.

Alexander is moving further and further away from answering the question posed last week by Sen. Patrick Leahy (D-Vt.), who wanted to know "how many times phone records obtained through Section 215 of the PATRIOT Act were critical to the discovery and disruption of terrorist threats." So far neither Alexander nor any other administration official has cited a single case that fits this description. Even when phone records help to flesh out a lead obtained through other means, it is not at all clear why the NSA needs to collect everyone's information in anticipation of that possibility, as opposed to seeking specific orders as the need arises. Consider how Alexander responded to that question yesterday:

Representative Adam B. Schiff, Democrat of California, pressed General Alexander to explain why the F.B.I. could not simply get the relevant logs of calls linked to a suspicious number without keeping a database of all domestic calls. General Alexander said he was open to discussing doing it that way, but added, "The concern is speed in crisis."

Seriously? All privacy safeguards represent an impediment to law enforcement; that's the whole idea. It is a bother to obtain a warrant before searching someone's house, but that does not mean we should dispense with that requirement in the interest of "speed" (although the courts do recognize an exception in the event of an actual emergency). Furthermore, the Foreign Intelligence Surveillance Court is designed to act swiftly, and it is hard to believe that any delay caused by seeking a Section 215 order would be the difference between stopping a "potential terrorist event" and allowing it to happen, especially since the foiled plots highlighted by the government tend to be half-baked schemes at best. Even Alexander does not seem to think that scenario is plausible; otherwise why would he be open to discussing a more targeted, less invasive approach to collecting phone records?

The difference between assembling everyone's phone records into a comprehensive database and seeking phone records relevant to a particular investigation is no minor detail. The indiscriminate nature of the NSA's phone record dragnet is the main basis for the constitutional and statutory arguments against it. Even Rep. James Sensenbrenner (R-Wis.), a co-author of the PATRIOT Act, complains that it goes beyond anything he and his colleagues meant to authorize. Yet here is the head of the NSA saying, in effect, that it might not be necessary after all.

That is consistent with the conclusions of Sens. Ron Wyden (D-Ore.) and Mark Udall (D-Colo.), who as members of the Senate Intelligence Committee should be privy to the relevant information:

After years of review, we believe statements that this very broad Patriot Act collection has been "a critical tool in protecting the nation" do not appear to hold up under close scrutiny. We remain unconvinced that the secret Patriot Act collection has actually provided any uniquely valuable intelligence. As far as we can see, all of the useful information that it has provided appears to have also been available through other collection methods that do not violate the privacy of law-abiding Americans in the way that the Patriot Act collection does.

They reiterated this point in response to Alexander's testimony at last week's hearing:

We have not yet seen any evidence showing that the NSA's dragnet collection of Americans' phone records has produced any uniquely valuable intelligence. Gen. Alexander's testimony yesterday suggested that the NSA's bulk phone records collection program helped thwart 'dozens' of terrorist attacks, but all of the plots that he mentioned appear to have been identified using other collection methods.

Deputy FBI Director Sean Joyce, who also testified at yesterday's hearing, likewise was unable to cite a single case in which the phone record database was crucial in stopping a terrorist attack. He called it "an almost impossible question," even while insisting that "every tool is essential and vital."