In April, the Electronic Frontier Foundation (EFF), the advocacy organization for citizens' digital rights, filed evidence to support its class-action lawsuit alleging that telecom giant AT&T gave the National Security Agency (NSA), the ultra-secret U.S. agency that's the world's largest espionage organization, unfettered access to Americans' telephone and Internet communications. The lawsuit is one more episode in the public controversy that erupted in December 2005, when the New York Times revealed that, following September 11, President Bush authorized a far-reaching NSA surveillance program that included warrantless electronic eavesdropping on telephone calls and e-mails of individuals within the United States.

Critics charged that the Bush administration had violated both the Constitution's Fourth Amendment, which protects citizens against unwarranted search or seizure, and the Foreign Intelligence Surveillance Act (FISA) of 1978, which requires eavesdropping warrants to be obtained from a special court of judges empowered for that purpose.

In February 2006, the controversy intensified. Reports emerged that component technologies of the supposedly defunct Total Information Awareness (TIA) project -- established in 2002 by the Pentagon's Defense Advanced Research Projects Agency (DARPA) to develop advanced information technology to counter terrorists, then terminated by Congress in 2003 because of widespread criticism that it would create "Orwellian" mass surveillance -- had been acquired by the NSA.

Washington's lawmakers ostensibly killed the TIA project in Section 8131 of the Department of Defense Appropriations Act for fiscal 2004. But legislators wrote a classified annex to that document which preserved funding for TIA's component technologies, if they were transferred to other government agencies, say sources who have seen the document, according to reports first published in The National Journal. Congress did stipulate that those technologies should only be used for military or foreign intelligence purposes against non-U.S. citizens. Still, while those component projects' names were changed, their funding remained intact, sometimes under the same contracts.

Thus, two principal components of the overall TIA project have migrated to the Advanced Research and Development Activity (ARDA), which is housed somewhere among the 60-odd buildings of "Crypto City," as NSA headquarters in Fort Meade, MD, is nicknamed. One of the TIA components that ARDA acquired, the Information Awareness Prototype System, was the core architecture that would have integrated all the information extraction, analysis, and dissemination tools developed under TIA. According to The National Journal, it was renamed "Basketball." The other, Genoa II, used information technologies to help analysts and decision makers anticipate and pre-empt terrorist attacks. It was renamed "Topsail."

Has the NSA been employing those TIA technologies in its surveillance within the United States? And what exactly is the agency doing, anyway?

The hearings that the Senate Judiciary Committee convened in February to consider the NSA's surveillance gave some clues. Attorney General Alberto Gonzales, maintaining the administration's defense against charges that it violated the Fourth Amendment and FISA, told senators, firstly, that Article II of the U.S. Constitution granted a president authority to conduct such monitoring and, secondly, that the Authorization to Use Military Force (AUMF) passed after September 11 specified that the president could "use all necessary and appropriate force" to prevent future terrorist acts. Regarding FISA, Gonzalez claimed, the NSA had sidestepped its requirements to obtain warrants for electronic eavesdropping in particular cases. But, overall, the attorney general said, FISA worked well and the authorities had used it increasingly. The available facts support Gonzalez's contention: while the FISA court issued about 500 warrants per year from 1979 through 1995, in 2004 (the last year for which public records exist) 1,758 warrants were issued.