Martha Radditz of ABC news asked the key question.

http://edition.cnn.com/2005/POLITICS/12/19/bush.transcript/index.html

QUESTION: You say you have an obligation to protect us. Then why not monitor those calls between Houston and L.A.? If the threat is so great and you use the same logic, why not monitor those calls?

Americans thought they weren't being spied on in calls overseas; why not within the country if the threat is so great?

BUSH: We will, under current law, if we have to. We will monitor those calls.

And that's why there is a FISA law. We will apply for the right to do so.

And there's a difference...

QUESTION: (OFF-MIKE)

BUSH: Let me finish.

There is a difference between detecting, so we can prevent, and monitoring. And it's important to note the distinction between the two.

QUESTION: But preventing is one thing. And you say the FISA laws essentially don't work because of the speed in monitoring calls overseas.

BUSH: I say we use the FISA courts to monitor calls. It's a very important tool and we do use it. I just wanted to make sure we've got all tools at our disposal.

This is an enemy which is quick and it's lethal. And sometimes we have to move very, very quickly. But if there is a need based upon evidence, we will take that evidence to a court in order to be able to monitor calls within the United States.