"I feel unable to fully evaluate, much less endorse, these activities," West Virginia Sen. Jay Rockefeller, the Senate Intelligence Committee's top Democrat, said in a handwritten letter to Vice President Dick Cheney in July 2003. "As you know, I am neither a technician nor an attorney."
Rockefeller is among a small group of congressional leaders who have received briefings on the administration's four-year-old program to eavesdrop — without warrants — on international calls and e-mails of Americans and others inside the United States with suspected ties to al Qaeda.
The government still would seek court approval to snoop on purely domestic communications, such as calls between New York and Los Angeles.
Cheney vigorously defended the program on Tuesday, saying "it's not an accident that we haven't been hit in four years."
He said he believes if there's any backlash coming because of the revelations about the surveillance program, it's "going to be against those who are suggesting somehow that we shouldn't take these steps to defend the country."
Some legal experts described the program as groundbreaking. And until the highly classified program was disclosed last week, those in Congress with concerns about the National Security Agency spying on Americans raised them only privately.
about the program at his final news conference of the year on Monday, reports CBS News chief White House correspondent John Roberts.
"I just want to assure the American people that, one, I've got the authority to do this; two, it is a necessary part of my job to protect you; and three, we're guarding your civil liberties," Mr. Bush said.
And he had harsh words for the officials who leaked the story – a devastating blow, he said, to national security.
"It is a shameful act by somebody who has got secrets of the United States government and feels like they need to disclose them publicly," he said.
Mr. Bush insists both the Constitution and congressional authorization for the war on terror give him the power to circumvent the courts when eavesdroping on suspected terrorists – and he says he is determined to keep doing it. But many scholars believe the program is utterly and completely illegal.
"I think their opinion is ludicrous," David Cole of Georgetown University said. "I think Congress expressly addressed whether the president could do this during war time and they said yes, but only for 15 days in an emergency situation. The president has now done it for four years."
Democrats charged that the president may have operated outside the law and tipped the balance of power, reports CBS News correspondent Gloria Borger.
"Where does he find in the Constitution the authority to tap the wires and the phones of American citizens without any court oversight?" Sen. Carl Levin, D-Mi., said.