White House officials launched a public defense of the National Security Agency domestic wiretap program. At the center of the defense is Attorney General Alberto Gonzales, who discusses the surveillance program. Sen. Patrick Leahy, D-Vt., who opposes the program, offers a response.

JIM LEHRER: The domestic surveillance debate: President Bush and other top administration officials have launched a major public campaign this week to give their side in the controversy. A central figure is Attorney General Alberto Gonzales. He is to make a speech on the subject tomorrow. I spoke with him earlier this evening.

JIM LEHRER: Mr. Attorney General, welcome. What is the basic message the president wants to deliver?

ALBERTO GONZALES: I think the message the president wants to deliver is that we are in a state of war against a very dangerous enemy and following the attacks of 9/11 he asked those of us in his administration to provide to him all the tools, all the lawful tools, that were available to him to fight this new kind of enemy.

The NSA advised the president that there was an additional -- some additional tools that we could provide to him in terms of electronic surveillance of the kind that he has now confirmed to the nation. The attorney general at that time confirmed to him that he had a legal authority to exercise -- to use this tool.

JIM LEHRER: You were the White House counsel at the time, right?

ALBERTO GONZALES: I was the White House counsel at the time.

JIM LEHRER: All right.

ALBERTO GONZALES: But, again, the attorney general at the time, General Ashcroft, the folks at the Department of Justice reviewed this program and provided a recommendation to the president that he did have the legal authority to do this.

And based upon the recommendation from the National Security Agency and, of course, the Department of Justice, the president decided this was something that he needed to do, he felt, in order to continue to make America safe.

JIM LEHRER: What was the reasoning behind not using the existing law, the Federal Intelligence Surveillance Act, as constituted?

ALBERTO GONZALES: Well, FISA has been very, very important. It's an extremely complicated statute, Jim. And it's been very effective in dealing with terrorists. And we've used it extensively in connection with the war on terrorism.

But for operational reasons, there were some issues that made it difficult to use FISA and --

JIM LEHRER: Like what, a timing problem, not enough time?

ALBERTO GONZALES: Again, I can't get into much of the details without divulging much of what the program that continues to remain classified.

But if we could have used FISA, of course, why wouldn't we have used FISA? It is a process that is tested and of course if we could have used FISA and felt that the country was secure, we would have used FISA.

JIM LEHRER: That's one of the basic questions here. You're saying that if FISA -- if you could have done what you wanted to do under FISA, you would have used FISA. But what you wanted to do, you could not use FISA?

ALBERTO GONZALES: What I'm saying is that there are operational constraints that existed upon the ability of our government to gather up information about terrorists that made it certainly more difficult to gather up electronic surveillance of the enemy.

And, again, I'm talking about a very limited focus program, Jim, where one avenue of communication has to be outside the United States, and we have to have a reasonable basis to believe that a party to the call is a member of al-Qaida or a member of an organization that is affiliated with al-Qaida.

There is a long history. Many, many presidents have exercised their inherent authority under the Constitution to engage in electronic surveillance of the enemy, particularly during a time of war. That's been long recognized by the courts and long recognized by practice.

Now, some would argue that in 1978 that that changed when FISA was passed, that that was intended to cabin the president's authority. Our response to that is, is that we have to look at the authorization to use military force, which was passed in the days following the attacks of 9/11, and we believe that the Congress intended for the president to engage in all of those activities that are fundamentally incidental to waging war, including electronic surveillance, and therefore we don't get to the question as to whether or not FISA is constitutional or unconstitutional.

Does it impinge upon the president's inherent constitutional authority as commander in chief that we have the permission by Congress? Congress has supplemented the president's constitutional authority in the authorization to use military force.

JIM LEHRER: Well, as you know, Mr. Attorney General, many present and former leaders of the Congress at that time when that resolution was being negotiated after 9/11 said that never even came up. They didn't in any way suggest or mean to suggest that the president had the right to go around FISA to electronic surveil people.

ALBERTO GONZALES: I would take you to the Supreme Court decision in Hamdi, the 2004 Supreme Court case. There, Mr. Hamdi contested the authority of the president to detain an American citizen in violation of an existing statute.

We argued that the authorization to use military force constituted permission by the Congress to do so. The Supreme Court agreed. And the Supreme Court said it is of no moment that the authorization to use military force does not mention detention. Detention of people captured on the battlefield is a fundamental incident of waging war. The same is true with respect to electronic surveillance.

JIM LEHRER: Well, you say -- there are a lot of people, as you know, not just Democrats -- legal scholars and others -- who question what this is doing to basic civil rights, the basic -- the right of a citizen to be free from surveillance by the government without going through a judicial process, which FISA required.

ALBERTO GONZALES: Well, again, I would repeat that this is a very limited program. We have a reasonable basis to believe that one party of the communication is a member of al-Qaida or a member of a group affiliated with al-Qaida.

And I would remind people that the president's authority here is not unchecked. We are still bound by the Constitution, by the Fourth Amendment. There are limitations under the Fourth Amendment with respect to engaging in this kind of surveillance.

JIM LEHRER: What do you say to those who say wait a minute there are three branches of government: there's the executive, which made this decision; there's Congress and there's also the judicial? Are you suggesting that this kind of decision is made solely by the president?

ALBERTO GONZALES: Absolutely not. What I'm saying is that Congress has played a role; in the authorization to use military force Congress has told the President of the United States, you may engage in all the activities that are fundamentally incidental to waging war. And that's the interpretation that the Supreme Court of the United States gave to the authorization to use military force so Congress has played a role.

JIM LEHRER: Do you think this is going to go to the courts before it's over to resolve this specific issue, whether that includes surveillance?

ALBERTO GONZALES: I don't know whether or not this is something that will go before the courts. The president has indicated that this is very important for the protection of this country.

I would add that if you listen carefully to the critics, there are none -- there may be a few, but if there are, there are very few, who have said stop the program.

What people are saying is we need to know what's going on here. And we need to get -- perhaps get Congress involved -- but no one has said stop this program because I think everyone understands that if someone is communicating with al-Qaida, someone here in the United States is communicating with al-Qaida, that the United States Government needs to know why.

JIM LEHRER: So, you're okay then with Congress passing new legislation that would either -- new legislation or amend the FISA law to bring this in to all kinds of -- to make it -- to make real sure it's legal and the critics have no more complaints?

ALBERTO GONZALES: Well, we believe that the Congress has already spoken on this issue. We do believe the president has inherent authority under the Constitution. We are obviously engaged now in a discussion with Congress, trying to advise Congress, educate Congress about what we're doing and we'll be engaged in a conversation with Congress about what is the appropriate way ahead in terms of ensuring that the civil liberties of all Americans protected but to do so in a way that we could continue to make America safe.

JIM LEHRER: Speaking of civil liberties, do you have any sympathy at all for the critics who have raised the civil liberties issue and say, hey, wait a minute, the president, no matter what you cite legally, should not have the right to go in without going through a court to do any kind of domestic surveillance? Do you have any -- not the legal part but just the uneasiness that this causes some people?

ALBERTO GONZALES: I'm always concerned about protection of civil liberties. I think it is one of the primary responsibilities of the Department of Justice, is to ensure that people's civil liberties are protected. Again this is a very carefully limited program. Gen. Hayden talked today about all of the safeguards in place in connection with the operation of this program. Gen. Hayden used to be head of the NSA.

JIM LEHRER: The NSA, right.

ALBERTO GONZALES: And so it's something that evaluated carefully, every 45 days or so, to ensure that the program continues to be needed and to ensure that the program is operating the way that the president has authorized.

JIM LEHRER: Who does the evaluating?

ALBERTO GONZALES: There are people within the NSA. Gen. Hayden talked about that in his remarks. The inspector general has been carefully involved in this program from day one. The general counsel's office of the NSA has also been very, very much involved in the scrutiny of this program.

JIM LEHRER: So no private citizen of the United States who has no connections directly or indirectly with al-Qaida or any other terrorist organization has anything to fear from what you all are doing?

ALBERTO GONZALES: What the president has authorized and only has authorized is the electronic surveillance of those communications where one call is outside the United States and where we have a reasonable basis to believe that a party of that conversation is a member of al-Qaida or a member of a group affiliated with al-Qaida.

JIM LEHRER: When you and the president and Attorney General Ashcroft and others were going over this after 9/11, did you anticipate there would be such a public firestorm if this ever got found out?

ALBERTO GONZALES: Electronic surveillance is something that is very, very, I think, sensitive. It can be very political. Of course, we understood that this would be something that some people would disagree with.

But the president made the decision that he had to do what was necessary in order to protect this country. And, quite frankly, I think it would have been irresponsible for anyone acting as president to not take action to further protect the country once he's told that we have the technology to do something and once the attorney general says yes you have the legal authority to do so.

JIM LEHRER: The debate that's going on now, do you consider it a legitimate debate in an open society?

ALBERTO GONZALES: I do consider it is a legitimate debate, absolutely. This is a very good debate we're having but it needs to be based on the facts, and part of the frustration here is that we're limited in what we can say publicly because if we talk much more about the operation of the program, we are going to educate our enemy about how we engage in surveillance over him. And we've known from previous experience when other sensitive programs have been disclosed, that our enemy changes tactics.

Our enemy is very patient and very diabolical. And they watch very carefully what we do. And so we very much worry that as there is more continued discussion about the operations, not the legal justification but the operations, that we may compromise the effectiveness of this program.

JIM LEHRER: Mr. Attorney General, thank you very much.

ALBERTO GONZALES: Thank you, Jim.