President Bush on Monday defended a program in which he authorized the National Security Agency to conduct real-time surveillance on persons in the U.S. with “clear links to al-Qaeda” and other terrorist groups, saying that he had the authority under law to authorize the program.

“Article II of the Constitution gives me that responsibility and the authority necessary to fulfill it. And after September the 11th, the United States Congress also granted me additional authority to use military force against al Qaeda,” Bush said at his year-end press conference Monday morning.

“Do I have the legal authority to do this? And the answer is, absolutely,” he said.

On Friday the New York Times revealed the existence of the NSA “special collection program” in which the NSA collects international communications of people in the U.S. with ties to terrorist groups, according to the Times. After initially refusing to confirm it, Bush confirmed the program’s existence Saturday and gave additional information on how the program works.

“Where does he find in the Constitution the authority to tap the wires and the phones of American citizens without any court oversight?” said Sen. Carl Levin (D-Mich.).

And Sen. Russ Feingold (D-Wis.), who led a filibuster against the renewal of the Patriot Act last week, said, “We will not tolerate a president who believes that he is the sole decision-maker when it comes to the policies that this country should have in the war against terror and the policies we should have to protect the rights of completely innocent Americans.”

Bush showed a great deal of emotion at the news conference, alternately appearing angered and appearing to plead with those watching to see things his way.

Bush emphatically denied he was trying to usurp power. “To say ‘unchecked power’ basically is ascribing some kind of dictatorial position to the President, which I strongly reject,” he said.

The program is reviewed about every 45 days “by the NSA Inspector General, by the NSA General Counsel, and by officials of the Justice Department who routinely look into this process and verify that the standards set out by the President are being followed,” said Deputy Director for National Intelligence Gen. Michael Hayden.

Attorney General Alberto Gonzales said that in addition to the September 14, 2001, joint resolution by Congress, the President’s order derives authority from a 2004 Supreme Court decision in Hamdi v. Rumsfeld, in which “Mr. Hamdi was a U.S. citizen who was contesting his detention by the United States government. What he said was that there is a statute, he said, that specifically prohibits the detention of American citizens without permission, an act by Congress — and he’s right, 18 USC 4001a requires that the United States government cannot detain an American citizen except by an act of Congress,” Gonzales said.

“We took the position — the United States government took the position that Congress had authorized that detention in the authorization to use force, even though the authorization to use force never mentions the word ‘detention.’ And the Supreme Court, a plurality written by Justice O’Connor agreed. She said, it was clear and unmistakable that the Congress had authorized the detention of an American citizen captured on the battlefield as an enemy combatant for the remainder — the duration of the hostilities. So even though the authorization to use force did not mention the word, ‘detention,’ she felt that detention of enemy soldiers captured on the battlefield was a fundamental incident of waging war, and therefore, had been authorized by Congress when they used the words, ‘authorize the President to use all necessary and appropriate force.’”

Bush said that the existing FISA court process was inappropriate to the type of surveillance being conducted, saying that “there is a difference between detecting so we can prevent, and monitoring. And it’s important to know the distinction between the two.” He said that FISA warrants were more appropriate to long-term monitoring.

Ryan Singel called the program “supremely illegal,” citing a 1972 Supreme Court decision in U.S. v. U.S. District Court in which President Nixon had ordered wiretaps on individuals suspected of plotting to bomb a CIA building, which said, “The Fourth Amendment contemplates a prior judicial judgment, not the risk that executive discretion may be reasonably exercised. This judicial role accords with our basic constitutional doctrine that individual freedoms will best be preserved through a separation of powers and division of functions among the different branches and levels of Government.”

In addition, comments by administration officials have led some to speculate that the NSA is using a different type of technology to conduct the surveillance in this particular program, or that it may have gained the cooperation of a communications hardware manufacturer.

I won’t speculate as to the nature of the program or what technology may be in use, but I will say that if President Bush doesn’t learn to keep his mouth shut, he’s going to leak the details himself. He inadvertently leaked one important operational detail during Monday’s press conference. And don’t ask me what it is; you can go watch for yourself.