hide captionPresident George Bush examines the devastation at the Pentagon with Secretary of Defense Donald Rumsfeld on Sept. 12, 2001, a day after a hijacked airliner slammed into the building.

President George Bush examines the devastation at the Pentagon with Secretary of Defense Donald Rumsfeld on Sept. 12, 2001, a day after a hijacked airliner slammed into the building.

When stories began to emerge about the U.S. government's massive surveillance of Americans' phone and Internet communications, it was no surprise to a group of analysts who had left the National Security Agency soon after the Sept. 11 attacks. Those analysts, who'd worked on systems to detect terrorist threats, left in part because they saw the NSA embarking on a surveillance program they regarded as unconstitutional and unnecessary.

Two of those analysts, Bill Binney and Kirk Wiebe, are interviewed in a Frontline documentary called United States of Secrets, which airs Tuesday night.

Binney was a cryptomathematician who worked as technical director of the NSA's World Geopolitical and Military Analysis Reporting Group.

Wiebe was a senior analyst who was awarded the NSA's Meritorious Civilian Service Award, the agency's second-highest honor.

Before the Sept. 11 attacks, Binney led a team that created a program called "Thin Thread," which could gather and analyze enormous amounts of Internet and telephone traffic and encrypt the identities of people in the U.S. so their privacy was protected.

Both Binney and Wiebe left the agency in 2001 after working there for decades and have publicly criticized the course the NSA has taken. Both were also eventually targeted in a leak investigation by the FBI that led to their homes being raided. After they left the NSA, they joined others in filing a complaint with the inspector general of the Defense Department about the agency's use of private contractors to develop a surveillance system the analysts regarded as expensive, ineffective and abusive of citizens' constitutional rights.

Binney, Wiebe and the documentary's director, Michael Kirk, spoke with Fresh Air's Dave Davies.

On the legality of the Bush White House approving new NSA measures after the Sept. 11 terrorist attacks

Link:

'Frontline' Doc Explores How Sept. 11 Created Today's NSA