How big a threat does ISIS pose?

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Fareed speaks with Admiral James Stavridis, former supreme allied commander at NATO and author of The Accidental Admiral, and Daniel Benjamin, a former coordinator for counterterrorism at the State Department and now director of The Dickey Center for International Understanding, about the threat posed by ISIS. Watch the video for the full interview.

Jim, it does feel like they've got their hands full, ISIS that is, between Iraq and Syria and all the forces that are battling them.

Stavridis: I think that this is a kind of a short-term/long-term set of constraints for us.

In the short-term, I completely agree, they've got their hands full. They've got Peshmerga coming from the north, they've got Iraqi security from the south, they've got bombing in the west. They're very busy. They're going to be in the middle of a three-front war very soon.

Long-term, there's not only, as Dan mentioned, I think ultimately the threat to the homeland – they have said they intend to fly the black flag of ISIS over the White House, I don't know how more direct they can be. But it is long-term.

You said, though, “it’s only a matter of time before a wave of EU-passport-bearing jihadists will be headed back home to wreak havoc.” So that sounds…

Stavridis: It's a matter of time. How long will that be? I don't know. Will it be different with individuals, different countries, different cultures? Absolutely. But that threat is building. It's a looming tower, as one person said about 9/11 a few years back.

Dan, one of the things they seem to be doing is goading the United States and the West. Presumably that is the point of these executions? That is the point of talking about raising the black flag. How seriously should we take this? People say one should have read Mein Kampf to understand Hitler's aims. So when they say all this stuff, how seriously do you take it?

Benjamin: Well, there's no question that they're no great fans of the United States, Fareed. I think that they were surprised a bit by the reaction to the decapitations. I think they probably miscalculated there. I think it's also important to calculate in here how much their presentation of themselves as hating the West, as being violently anti-American, is really aimed at selling themselves to potential recruits.

They’ve gone out of their way to prove that they are the most brutal group anyone has seen. And this has really worked for them. It's attracted an awful lot of people to their cause.