Gonzales was the second administration official in two days to attack athat the program was unconstitutional. Vice President Dick Cheney on Friday called the ruling "an indefensible act of judicial overreaching."
Gonzales told about 400 cadets from the Air Force Academy's political science and law classes that some see the program as on the verge of stifling freedom rather that protecting the country.
"But this view is shortsighted," he said. "Its definition of freedom — one utterly divorced from civic responsibility — is superficial and is itself a grave threat to the liberty and security of the American people."
Gonzales and Cheney's attacks on the court order came as the administration was urging the lame-duck Congress to approve legislation authorizing the warrantless surveillance. The bill's chances are in doubt, however, because of Democratic opposition in the Senate, where 60 votes are required to end debate and vote.
At a news conference, Gonzales would not speculate how the administration would react if Congress did not authorize warrantless surveillance.
"We're optimistic because of the importance of this program, the success of the program, the stated commitment of the Democratic leadership to work with us in protection of America, and that we're going to have a good discussion and dialogue about the program," he said.
"We believe the president has the authority under the authorization of military force and inherent authority of the constitution to engage in this sort of program, but we want to supplement that authority," he said.
The administration has maintained that its warrantless surveillance program focuses on international calls involving suspected terrorists, and dismisses charges that it is illegal because it bypasses federal law requiring a judge-issued warrant for such eavesdropping.
"It's absolutely essential that we maintain the tool," he told reporters. "It's been very, very important in protecting America, and we look forward to working with Congress to find a way that we can supplement the president's authority, and continue to maintain this as a valuable tool for the American people."
In August, the program was struck down by U.S. District Judge Anna Diggs Taylor in Detroit, who said it violated the rights to free speech and privacy and the constitutional separation of powers. She was the first judge to rule on the legality of the program, which is operated by the National Security Agency.
The government has appealed. Bush and other administration officials argue that the program is legal under the president's constitutional powers and has saved lives by helping to disrupt terrorist plots.
Speaking to the cadets, Gonzales dismissed as "myth" the charge that civil liberties were being sacrificed in the fight against terrorism. He defended the Patriot Act and the handling of detainees at the U.S. military base at Guantanamo Bay, Cuba.
"To achieve victory at the cost of eroding civil liberties would not really be a victory. We cannot change the core identity of our nation and claim success," said Gonzales, an Air Force veteran who attended the Air Force Academy from 1975 to 1977.