CHRIS WALLACE: Let's talk about a current threat, Iran. What if the talks fall apart and there is no deal? What's your best intelligence? Will Iran race to develop a nuclear weapon? Or are they more likely to go back to where we were before the talks, just a couple of months short of breakout?
JOHN BRENNAN, CIA DIRECTOR: The nuclear program is one issue that we're hoping to be able to halt, but also we see that Iran is still a state-sponsored terrorism. So what we have to do -- whether there's a deal or not -- is to continue to keep pressure on Iran and to make sure that it is not able to continue to destabilize a number of countries in the region.
WALLACE: I want to get into that in a moment. On the deal, what's your guess what happens if there is no deal? Do they breakout or do they stay just short of that?
BRENNAN: I think they realize there will be tremendous costs and consequences and implications if they were to decide to go for a breakout. There are a number of things that the United States has available to it to prevent Iran from getting a bomb. President Obama has made it very clear that we are going to prevent Iran from having that type of nuclear weapon that they may were going on the track to obtain.
So, if they decide to go down that route, they know that they will do so at their peril.
WALLACE: On the other hand, if there is a deal, the big question is, can we verify that Iran is living up to that deal?
Here is what Israeli Prime Minister Netanyahu told Congress.
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BENJAMIN NETANYAHU, ISRAELI PRIME MINISTER: Iran not only defies inspectors, it also plays a pretty good game of hide and cheats with them.
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WALLACE: Question, how confident are you that between the new inspections regime under the agreement and your intelligence in the area that you would be able to ensure that Iran was not secretly building a nuclear weapon?
BRENNAN: It's not a question of trusting the Iranians on this. I know that Secretary Kerry and President Obama are comfortable with what it is that we are insisting on as far as a verification regime.
WALLACE: But, frankly, our track record when it comes to Iran and its nuclear program is not good. Iranian opposition groups in 2002 were the ones that revealed that the regime had secret facilities at Natanz in Iraq. One of your predecessors, Michael Hayden, says that they had done a lot of work at Fordo before we knew about it.
Fact is, they fooled us, repeatedly, the Iranians.
BRENNAN: And I think we've gone to school on some of those developments over the last decade or so, so that we can now have a better plan and opportunity to verify some of the things that they are saying they are going to do and not do.
WALLACE: Are you aware of an underground site near Tehran called Lavizan-3?
BRENNAN: I know that there are a lot of reports. I'm not going to get into what it is we know about the Iran nuclear program. But I am confident that our intelligence capabilities are sufficiently robust that we have a good understanding of what the Iranian nuclear program entails.
WALLACE: Well, the reason I ask is Iranian opposition groups say that there is a secret nuclear facility there that we haven't known about.
BRENNAN: I think we have confidence that we're aware of the facilities that Iran has right now, and there's going to be a lot of speculation and rumors about other facilities. But, again, I'm confident that right now, we have a good appreciation of what the Iranian nuclear program consists of.
WALLACE: What is the danger of nuclear arms race across the Middle East? Top Saudi officials, including former intel chief, Prince Turki al Faisal, say if there's a deal, that the Sunni nations are going to match whatever it is we allow the Iranians to do. Doesn't that just lead to an arms race?
BRENNAN: We talked to the Gulf partners. We're trying to stay close in touch with them. I believe that they do have confidence that the United States is going to be sort of the security guarantor in that region to prevent this type of escalation that's going to include nuclear weapons.
WALLACE: But when you have top Saudi officials say they're going to top what we have Iran have, doesn't that create an arms race?
BRENNAN: We continue to have this close dialogue with them, about what it is that we are insisting upon, from the Iranians and the verification system there. So, I'm confident that the Saudis will be a responsible partner and player in the region.