Updated

The following is a rush transcript of the May 9, 2010, edition of "Fox News Sunday With Chris Wallace." This copy may not be in its final form and may be updated.

CHRIS WALLACE, ANCHOR: Last week's attempted bombing in Times Square has produced a flood of questions about how to prevent more terrorist attacks on this country. Joining us now is John Brennan, the president's top counterterrorism adviser.

And, Mr. Brennan, welcome back to "Fox News Sunday."

JOHN BRENNAN, WHITE HOUSE COUNTERTERRORISM ADVISER: Thank you, Chris.

WALLACE: Let's start with Faisal Shahzad, the alleged Times Square bomber. He has reportedly told authorities that he was trained by Pakistani Taliban commanders. On the other hand, General David Petraeus, head of U.S. Central Command, says Shahzad was a lone wolf who did not have direct contact with terrorists.

Question: What's your best understanding of this?

BRENNAN: OK. Well, first of all, I want to wish a happy Mother's Day to all those mothers out there, who — many of them who are saving — serving in defense of this country.

Mr. Shahzad, who attempted to carry out the attack in Times Square — it looks as though he was operating on behalf of the Tehrik-e Taliban Pakistan. That's the TTP. That's the Taliban within Pakistan. This is a group that is closely allied with Al Qaeda. It has a murderous agenda similar to Al Qaeda. They train together. They plan together. They plot together. They're almost indistinguishable.

This is something that we are looking at right now in terms of the investigation, understanding exactly who Mr. Shahzad worked with and the extent of his training as well as his interaction with individuals whether they be here in the United States or overseas.

WALLACE: Do we believe he was trained by the Pakistani Taliban?

BRENNAN: Yes, we do.

WALLACE: Do we believe that he was funded by the Pakistani Taliban?

BRENNAN: It appears as though he was.

WALLACE: Do we believe that he met with top Pakistani Taliban leaders like Hakimullah Mehsud and their bomb chief, Qari Hussein?

BRENNAN: He had extensive interaction with the TTP. And this is something that we are, again, looking at very carefully, understanding the extent of that interaction and the extent of the direction and guidance that was given to him.

WALLACE: Do we believe that this was as a result or a response to U.S. drone attacks against the Taliban in Pakistan?

BRENNAN: The TTP has, as I said, been working with Al Qaeda for a number of years since it was created several years ago. They have targeted U.S. interests and Pakistani interests in Pakistan. They have threatened to carry out attacks against us including here in our cities.

So this is something that has been on their agenda and they're determined to carry out those attacks. That's why we have to guard against them as well as all these other groups that have aligned with Al Qaeda.

WALLACE: One more factual question. Do we believe that Shahzad became a U.S. citizen so he could travel back and forth to Pakistan more easily to carry out these attacks?

BRENNAN: Well, he clearly traveled back and forth to Pakistan numerous times. The motivation for his citizenship I'm not able to speak to. But he then was able to acquire U.S. citizenship and — which facilitated his travel back and forth.

WALLACE: Well, if the links are as strong as you are — lead us to believe, what are we going to do about it?

BRENNAN: Well, we're going to maintain the pressure that we've been putting on Al Qaeda and these groups in Pakistan. We're working very closely with the Pakistani officials. They've been very cooperative in this investigation.

It underscores the determination of this ruthless enemy, but also it underscores the importance for us to maintain our vigilance, not to be complacent, keep the pressure on them, find them and capture them, arrest them or kill them if we can.

WALLACE: In a sense, does that mean a new escalated offensive against the Pakistani Taliban?

BRENNAN: No. Again, this just illustrates that they are going to continue to try every day to find vulnerabilities in our defenses. That's why we have a redundant system in place. That is why we have been carrying out a determined effort with Pakistan, and inside of Pakistan and Afghanistan, to degrade their capabilities.

I think the lack of sophistication, lack of capability, on their part demonstrates that we've been very successful because they're no longer able to carry out those large attacks.

They're still trying to do it. We have to be vigilant against them. But these one-off — these types of attacks that we see Najibullah Zazi as well as Shahzad carrying out — I think it reflects their inability to plot, plan, and carry out these attacks successfully in a sophisticated manner.

WALLACE: Secretary of State Clinton is now warning Pakistan of, quote, "very severe consequences" if a successful attack were traced back to insurgent groups inside Pakistan. First of all, what do you want Pakistan to do? And secondly, what kind of consequences if they don't?

BRENNAN: We've been working very closely with the Pakistanis to make sure that we're able to utilize our intelligence resources that we have, so we can find out where they are, capture them, arrest them, interrogate them.

The Pakistanis, as I said, have been cooperative, particularly in this investigation. They need to maintain the pressure on all of these groups. There are no militant or terrorist groups in Pakistan that should be allowed to continue there.

They've moved into Waziristan. They need to continue to apply the pressure there, along the border, as well as in other areas. There are a number of terrorist groups and militant organizations operating in Pakistan, and we need to make sure that there's no support being given to them by the Pakistani government.

We will continue this dialogue. The Pakistanis understand the seriousness of this. And we are going to continue to interact with them but also maintain pressure on them and inside of Pakistan.

WALLACE: Some top Republicans are saying that the administration has been more lucky than good in some of these terror cases, given that both Shahzad and the Christmas Day attempted bomber Abdulmutallab both detonated bombs that just failed to go off.

Do you consider the Times Square attack a success for Homeland Security?

BRENNAN: I consider that Homeland Security, law enforcement, intelligence and the military have done an outstanding job since 9/11.

You know, when I hear these references to being lucky, tell that to the hundreds of thousands of American men and women who are serving in Afghanistan and in other parts of the world, who are at our points of entry, who are working around the clock here in the United States and abroad. That's not luck. That's patriotism. That's dedication. That's capability and talent.

And so we've been able to stop them in their tracks. They are determined. They are going to continue to look for opportunities to get here to the United States. This is something that they have pledged to do. I think we have a very strong track record, and that's why we have redundant capabilities in place.

We're not lucky. We're good.

WALLACE: But in fairness, you haven't stopped them in their tracks, sir. Over the last six months we had Nidal Hasan, the Army major who went on a shooting spree at Fort Hood. We had Abdulmutallab, who was able to get on a plane on Christmas Day and set off a bomb that just failed to go off, but he was able to set it off. And then we have this guy who traveled back and forth to Pakistan, put a car bomb on a Saturday night in Times Square and set it off. Failed to go off. You didn't stop them in their tracks.

BRENNAN: We've stopped many, many operations, terrorist plots, from taking place here in the United States and overseas. On a daily basis we are being successful finding them, arresting them, killing them, stopping these types of attacks.

Sometimes they're able to penetrate those fences, get in here, take advantage of citizenship, other types of opportunities here. We need to maintain our vigilance. We need to make sure that we're not going to be complacent at all. And we're bringing to bear all of the tools that we have in our arsenal. We'll continue to do this.

This is going to be a long effort and a long war. We're determined to do it. We're going to continue. We're going to learn the lessons that — from Abdulmutallab, from the Times Square incident, and refine our system as needed and move forward.

WALLACE: But how do you explain — as the president's top counterterrorism adviser, how do you explain the fact that in the last six months there have been three times when terrorists in this country have launched attacks before you've been able to stop them?

BRENNAN: Right. We're a country of, what, 300 million people. We are a country that thrives on the freedoms and liberties that make this country so great. So there are people within the United States. Sometimes they are attracted to this venomous rhetoric that is coming out from Al Qaeda and other individuals overseas.

We need to make sure that we're able to find them. But there are things that can take place in this country that are going to be outside of the radar of law enforcement, Homeland Security, intelligence officials. We need to maintain this vigilance. We need to work very closely with law enforcement to ensure that they're not able to carry out these successful attacks.

WALLACE: After the Christmas Day bombing, President Obama's initial response was to call Abdulmutallab an isolated extremist. And here's what Homeland Security Secretary Napolitano said last Sunday about the Times Square bombing. Take a look.

(BEGIN VIDEO CLIP)

HOMELAND SECURITY SECRETARY JANET NAPOLITANO: Right now we have no evidence that it is anything other than a one-off.

(END VIDEO CLIP)

WALLACE: Question: Why is this administration's first response to play down these attacks?

BRENNAN: I don't think it's an attempt to play down. What we're trying to do is to be open with the American public, trying to let them know what we know at those times. These investigations are ongoing.

Within 53 hours we were able to bring successfully this investigation to the point where we were able to find him, stop him and then bring him into custody — tremendous interaction among — and coordination of all the different elements that have been brought to bear on this effort.

So Secretary Napolitano and others — what they're trying to do is to engage the American public. We also want to send a reassuring message to the American public that we're doing everything possible to find out what is out there and to stop them as we can.

WALLACE: There's no question that extraordinary police work was done to catch this guy in 53 hours. There's no question about that.

But is it reassuring to the American public when the president calls Abdulmutallab an isolated extremist and he turns out not to be, when Secretary Napolitano last Sunday says this is a one-off, and you're here this Sunday to tell us he was integrally involved with the Pakistani Taliban?

BRENNAN: Well, I think in the — in each case there, they were individuals who were operating on behalf of a larger organization and to try to carry out those attacks on behalf of this agenda.

Abdulmutallab was a singleton on that plane, but he obviously had the links back to Al Qaeda in the Arabian Peninsula. Shahzad in Times Square had links back. But he drove that vehicle to Times Square alone.

WALLACE: How long did authorities question Shahzad under the public safety exception, the so-called ticking time bomb exception, before they read him his Miranda rights?

BRENNAN: He was debriefed, interrogated, for several hours. That's under the public safety exception, under Quarrels. He was read his Miranda rights then. He waived those rights to counsel. The questioning continued. We are continuing to get important information from him. And the investigation is ongoing.

WALLACE: We've been told three to four hours, is that correct?

BRENNAN: That's approximately correct, yes.

WALLACE: How — you didn't obviously know — excuse me — when you read him his Miranda rights that he was going to keep talking. How did you decide after four hours that you had gotten all the information you needed about any current plots, particularly now that you find out that he was involved and directed by the Pakistani Taliban?

BRENNAN: I don't think we felt as though we got all the information we needed, but we also recognized that there are certain obligations under the U.S. law and the Constitution and the Supreme Court decisions that certain actions should be taken.

And so this is a U.S. citizen who was captured here in the United States, and so the investigating officers, the FBI and others, worked according to those rules and obligations, very successfully. And so it did not impede our ability to continue to acquire very important intelligence from him.

It was, I think, a very good example that law enforcement, operating within those — within the existing system, were able to leverage the opportunities that they had to get this information.

WALLACE: Was the advice that you could not question him under the public safety exception any longer?

BRENNAN: The FBI works with the Department of Justice. We had consultations within the intelligence community and with the FBI as we were looking at this case, from the first moment that it occurred, so we had that consultation. We knew what we were trying to find out from him under the public safety exception. And it was a very good activity and interaction that we had.

WALLACE: We're going to be talking with Senator Joe Lieberman in a moment. And he now wants to change the law to strip U.S. citizenship of any American who provides material support for a foreign terrorist group. Is that a good idea?

BRENNAN: I will leave it to the constitutional scholars as well as to the right people within the legislative and executive branches to determine the feasibility and advisability of that.

I am most interested in taking these people off of the streets, off of the battlefield — again, finding them, arresting them, capturing and killing them. That is the best way we're going to be able to protect the American people as well as people worldwide from the scourge of international terrorism.

So what I'm trying to do is to stay focused on finding them and doing everything possible to prevent them from successfully carrying out these attacks.

WALLACE: This week, Attorney General Holder continued to say that the trial of Khalid Sheikh Mohammed and the other 9/11 co-defendants could — could — be held in New York City. Let's watch what he had to say.

(BEGIN VIDEO CLIP)

ATTORNEY GENERAL ERIC HOLDER: We are considering a number of options with regard to where that trial might be held, and I'll leave it at that.

UNIDENTIFIED MALE: But New York is still among those that you're considering?

HOLDER: I indicated that before. Yeah.

(END VIDEO CLIP)

WALLACE: Why keep saying that?

BRENNAN: Because the decision hasn't been made, so therefore...

WALLACE: But...

BRENNAN: ... by definition all the options are on the table.

WALLACE: But, Mr. Brennan, you know there's no chance that you're going to hold this trial in New York City.

BRENNAN: What we are trying to do is now determine how best to bring KSM to justice in the swiftest manner possible. There are certain constitutionally-based requirements as far as venue is concerned, whether the determination is made for Article III or for military commissions.

These are deliberations that are taking place right now. So until that decision is made, I think it would be foolhardy to take off of the table any of these prospective courses or venues.

WALLACE: Do you think — after the mayor says he doesn't want it, after senators say they don't want it, after the Times Square attack, do you think it's reasonable to even consider holding the trial of KSM in New York City?

BRENNAN: I think it's reasonable to look at every option out there and to find the best way to bring that murderer to justice.

WALLACE: Even in New York City?

BRENNAN: Wherever it can be done. And we're working with the Congress, we're working with local jurisdictions and we're working with the Department of Justice and others to bring him to justice.

WALLACE: On a separate matter, is the government investigating whether the 1,000-point drop on Wall Street on Thursday could have been a cyber attack?

BRENNAN: There's no indication that it was.

WALLACE: So that's...

BRENNAN: To my knowledge, not at all. I mean, they're looking at the causes for that. I know that. So they are looking at whatever possibilities that were out there, but to my knowledge there's no indication that it was.

WALLACE: Finally, what's the biggest lesson that you have learned from the Times Square case? What's the biggest security gap that you see that you think, "We've got to fix that?"

BRENNAN: I think the lesson is, as I said before, we need to maintain this vigilance. We need to not feel reassured in any way because there hasn't been a successful attack here in so many years.

The interaction between local law enforcement, like the NYPD and the FBI, is critically important. We rely heavily on vigilant citizens, as was demonstrated in the Times Square case, in the Abdulmutallab case, and in the Najibullah Zazi case as well — bringing these, you know, concerns to our attention, making sure that we're able to follow up on them very quickly and having a system in place where we can respond rapidly, find these individuals and make sure that they do not try to attempt to hurt us again.

WALLACE: Mr. Brennan, we want to thank you so much, as always, for coming in. Please come back, sir.

BRENNAN: Thank you, Chris.

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