Let's get more on the crisis in Iraq. Officials estimate that the Isis militants have about 2,000 fighters with passports to enter the United States without a Visa. In my exclusive interview with... See More
Let's get more on the crisis in Iraq. Officials estimate that the Isis militants have about 2,000 fighters with passports to enter the United States without a Visa. In my exclusive interview with president owe ma bah ma, he conceded that the threat they pose is growing. I think we have been under serious threat my entire presidency. I think we have been under serious threat pre-dating 9/11 from those who embrace this ideology. They're gaining strength, aren't they? In some places. We have seen europeans sympathetic to their cause traveling into Syria. May now travel into Iraq. Getting battle-hardened. Then they come back. They have a european passport. They don't need Visas to get into the United States. We are spending a lot of time, and we have been for years, making sure we are improving intelligence to respond to that. We have to improve the surveillance. Reconnaissance intelligence there. Special forces are going to have a role. There will be times we take strikes against organizations that could do us harm. Let's get more from peter king. From the house committee on homeland security. And ABC's chief global affairs correspondent, Martha Raddatz, just back from Iraq. And congressman king, let me begin with you. You saw the president. What is the biggest danger? He should not just be conceding it. This is a real, real threat. There's nothing to concede. He should be very aggressive on this. Syria is our biggest threat. Not only are there thousands of europeans have Visas to get into the united States going to Syria. But there are 100-plus Americans over there in Syria right now. Any of them can come back to the United States and carry out the type of attack they're being trained in in Syria. The terrorists in Syria are sophisticated. Advanced. And so thousands of people can go back to Europe and come back here. Only one or two of them, we could have a lethal attack in the U.S. We saw that American carry off a suicide bombing in Syria a few weeks back. Pierre also talked about U.S. Officials asking overseas airports to enhance security. What is going on with that? I can't go into details. It is very important to deal with. Because, a number of airports do not have the type of security they should have. Anyone that will be having someone to fly to the U.S., they have to increase their security. We're going to be pushing it. I can't go into all the details. Overseas airport security is something we're concerned about. It's something we're keeping a real eye on. We are. We should be aggressive. So the American people know how real this threat is. So much support coming in for the Iraqi military. The Iranians are helping them. The Syrians are launching air strikes. We saw this morning Russian flight -- fighters going in. Russian fighter jets, yeah. And we know the U.S. Advisers are on the ground. What difference are they making? They have to assess what is going on. I think a bigger help is the intelligence. The drones that are flying. The surveillance aircraft. They're giving the Iraqis a sense of where things are happening, in tikrit, where the Iraqi military is trying to move in and root out Isis where they've had success. 'S back and forth who is in control of the city. Once the advisers establish what is going on and how they can help will really go outside of the embassy, that is where they can really start helping. Start telling the Iraqi military, can help them more with command and control and morale. That is the amazing thing they saw there. An absolute collapse of the morale in the Iraqi soldier forces. Soldiers running away. Sold yours running away. Once they started running away, there was a tidal wave. When I talked to the president earlier in the week, he didn't say he was ready to order air strikes. What does he have to hear before he acts? Well from the Iraqi government, he has to have a sense that they're not just going after Sunnis. The minority Sunnis. They have to hear that the Iraqis are being careful. They, too, are not ordering air strikes just on their enemies. I think there is a series now, of things that have to happen before the United States is involved in air strikes. I don't think they're quite close to that. Obviously, if the Americans were threatened, the embassy, they could do something about it, they would probably take action or if there was a very easy target perhaps out in the desert, they would take action. But any air strikes, I don't think you'll see it. I think the U.S. Is concerned about the embassy, the airport. I think the U.S. Will take the security acts necessary to protect the Americans there, the assets that are there. I think the president, on that, he can count on support, I believer, from republicans in congress to do whatever it necessary to protect the Americans. Does the president have all the authority he needs from congress right now to act? They may ask for additional powers. I'm not someone who is totally addicted to the war powers act. I think the president, to play it safe, any additional assets, or troops, forces, I think he'll go to the congress. Peter king, Martha Raddatz, thank you very much.
This transcript has been automatically generated and may not be 100% accurate.