Secretary of State John Kerry said of ISIS foreign fighters “we don’t know how many people precisely there are who have filtered their way back in” but that he is “convinced that we are slowly and steadily deteriorating Daesh’s ability to recruit, it’s ability to prosecute” in an interview aired on Friday’s broadcast of CNN’s “Wolf.”

Kerry, in response to a question on whether foreign fighters from Syria attacking the US was a possibility, stated, “Well, it did in San Bernardino. I mean, we saw somebody come back, radicalized, and go on a killing spree. So, everybody understands that any of these foreign fighters who have come back still attached to Daesh. Now, many people have left Daesh, recognizing that it was a lie, that all the things they’d been told were lies. Some of those people who tried to get away were executed. Others managed to get away, and they’ve come back to tell the story of the lie. So, we don’t know how many people precisely there are who have filtered their way back in. But, I believe very deeply, that as we put additional pressure on Daesh in Syria, and Iraq, it is entirely possible that in some other part of the world, people will lash out out of desperation.”

Kerry was then asked if he was concerned with Brussels-style attacks on the US. He responded, “Let me put it to you this way, law enforcement, and intelligence community people have to get it right, to prevent an attack, every minute of every day, 24 hours a day, seven days a week, 365 days a year. If somebody wakes up one morning in their apartment and decides they want to go out and kill themselves and take some people with them, they can most likely find a place, on a subway, on a bus, in a market, somewhere to do it, unfortunately. So, there’s a very — you know this is a difficult challenge, and frankly, it’s quite remarkable that our law enforcement community, our intelligence community, our police, have done as good a job as they have done, of protecting us here, both in America, as well as in other parts of the world. Now, that doesn’t excuse one single event. When it happens, everybody’s focused on it with the intensity that we see here in Belgium right now. But I am convinced that we are slowly and steadily deteriorating Daesh’s ability to recruit, it’s ability to prosecute, it’s Neolithic ideology, and over time, we are going to get back to a world where we feel that we can travel with impunity and feel safe.”

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