In a press conference from the White House this morning -- his third live televised event in three days -- George W. Bush tried to defend his decision to engage in warrantless spying on Americans citizens, all the while condemning those government officials who exposed the controversial program to public view in the first place.

Bush said it was a "shameful act" for anyone to reveal that he had authorized the National Security Agency to eavesdrop on telephone calls without warrants, and he said he assumed that the Justice Department was taking the steps necessary to begin an investigation into leaks of classified information. At the same time, he suggested that he would oppose any congressional investigation into the spying program itself. "The fact that we're discussing this program is helping the enemy," Bush said.

The president didn't explain -- the president can't explain -- why. The Foreign Intelligence Surveillance Act allows the executive branch to monitor telephone calls and other electronic communications so long as it obtains a warrant for doing so. If al-Qaida is paying as much attention as Bush suggests, it already knew that much, and it has "adjusted" -- Bush's term -- to that knowledge accordingly. What Bush's program for spying did was remove the warrant requirement FISA imposes. How does that change anything for al-Qaida? How would terrorists communicate differently if they knew that the National Security Agency might be monitoring them without a warrant instead of with one? There's no good answer to that question, and Bush didn't give one.

Bush also failed to explain, at least in any way that made sense, why he needed to evade FISA's requirements. Bush said repeatedly that the war on terror is a new kind of war that requires fast action by the United States. "This is a different era, a different war, it's a war where people are changing phone numbers and phone calls, and they're moving quick," he said. "We've got to be able to prevent and detect. It requires quick action."

But the FISA process was designed for quick action. And indeed, FISA allows the executive branch to begin monitoring communications immediately and then seek a warrant after the fact. How isn't that "fast" or "quick" or "agile" enough? Bush couldn't say. Instead, he suggested again and again that the FISA process is for "long-term monitoring" and that, after the attacks of 9/11, he saw the need to "detect." He never explained what he meant by that or how the FISA process couldn't be used both to "monitor" and to "detect."

It wasn't at all clear that he knew. And if he knew, he certainly wasn't saying. Bush said he wouldn't get into details about the secret spying program because doing so would help al-Qaida. Americans would simply have to trust him, he said, trust that he's doing everything he can to protect them from attack while respecting their civil liberties.