The NSA director confirmed to Congress today that leaker Edward Snowden had access to a highly sensitive database containing personal information that could be mined to track a target’s thoughts and actions and possibly predict future acts.

U.S. Army General Keith B. Alexander, commander of U.S. Cyber Command and director of the National Security Agency, told the Senate Appropriations Committee that Snowden “had great skills as an IT (Internet Technology) system administrator.”

Alexander’s explanation came in response to a query by Sen. Dick Durbin, D-Ill., about how Snowden had advanced to trusted access to a treasure trove of secret NSA information. The 29-year-old had dropped out of high school and failed in his military experience, only to end up working for three months as a Booz Allen Hamilton employee in Hawaii under a contract with the NSA.

Alexander confirmed that Snowden, as a system administrator for Booz Allen, had access to “a wide range of sensitive NSA information.”

Responding to Snowden’s claim that he could wiretap any phone call in the United States, Alexander said that’s false.

“I know of no way to do it,” the NSA chief said.

In defense of NSA surveillance activities, Alexander claimed the NSA data collection has prevented dozens of “critical” terrorist events.

“We are less secure than we were two weeks ago,” Alexander further claimed, arguing Snowden’s leaks had jeopardized national security.

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