"Surveillance of American phone metadata has had no discernible impact on preventing acts of terrorism and only the most marginal of impacts on preventing terrorist-related activity, such as fundraising for a terrorist group.... The overall problem for U.S. counterterrorism officials is not that they need vaster amounts of information from the bulk surveillance programs, but that they don't sufficiently understand or widely share the information they already possess that was derived from conventional law enforcement and intelligence techniques."
On June 5, 2013, the Guardian broke the first story in what would become a flood of revelations regarding the extent and nature of the NSA's surveillance programs. Facing an uproar over the threat such programs posed to privacy, the Obama administration scrambled to defend them as legal and essential to U.S. national security and counterterrorism. Two weeks after the first leaks by former NSA contractor Edward Snowden were published, President Obama defended the NSA surveillance programs during a visit to Berlin, saying: "We know of at least 50 threats that have been averted because of this information not just in the United States, but, in some cases, threats here in Germany. So lives have been saved." Gen. Keith Alexander, the director of the NSA, testified before Congress that: "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." Rep. Mike Rogers (R-Mich.), chairman of the House Permanent Select Committee on Intelligence, said on the House floor in July that "54 times [the NSA programs] stopped and thwarted terrorist attacks both here and in Europe – saving real lives."
However, our review of the government's claims about the role that NSA "bulk" surveillance of phone and email communications records has had in keeping the United States safe from terrorism shows that these claims are overblown and even misleading. An in-depth analysis of 225 individuals recruited by al-Qaeda or a like-minded group or inspired by al-Qaeda's ideology, and charged in the United States with an act of terrorism since 9/11, demonstrates that traditional investigative methods, such as the use of informants, tips from local communities, and targeted intelligence operations, provided the initial impetus for investigations in the majority of cases, while the contribution of NSA's bulk surveillance programs to these cases was minimal. Indeed, the controversial bulk collection of American telephone metadata, which includes the telephone numbers that originate and receive calls, as well as the time and date of those calls but not their content, under Section 215 of the USA PATRIOT Act, appears to have played an identifiable role in initiating, at most, 1.8 percent of these cases. NSA programs involving the surveillance of non-U.S. persons outside of the United States under Section 702 of the FISA Amendments Act played a role in 4.4 percent of the terrorism cases we examined, and NSA surveillance under an unidentified authority played a role in 1.3 percent of the cases we examined.