An American killed fighting FOR ISIS – how far and deep is the terror group’s reach?

CATHERINE HERRIDGE, FOX NEWS CHIEF INTELLIGENCE CORRESPONDENT: … the American citizen killed in Syria was known to the U.S. government and his affiliation also with ISIS. The FBI is tracking dozens of cases of Americans traveling from the U.S. to Syria. And the TSA has instituted new security measures, which help it rack individuals of interest for returning from the region to the United States within 72 hours of their flight. But that system does not flag everyone.

VAN SUSTEREN: Was this man of sufficient interest that he would have gotten caught?

HERRIDGE: He was of significant interest to the U.S. government and they had been tracking him, it’s now clear to me, for several months.

The interesting continuing thing to me tonight is when the National Security Council put out a statement about his death, they said it was evidence that Americans should not travel to Syria. What they neglected to mention is that he was fighting for ISIS. And this is not a mistake. This is an act of commission.

HERRIDGE: I don’t know. But I think that you do see a pattern often where the affiliation with known terrorist groups is dropped. And it takes me back to the original reporting we did on Major Nidal Hasan and the Fort Hood massacre where that was classified as work-place violence and a great effort to distance him from his al Qaeda affiliation with a cleric in Yemen.

VAN SUSTEREN: Catherine just reporting this very disheartening news. Douglas McCain, an American, fighting for ISIS, but NSC gives us a travel warning and doesn’t want to say that he is working with ISIS or was working with ISIS.

NORTH: Douglas McAuthur McCain was his adopted name. When you are looking at now two in a week, the Brit who murdered James Foley, and now an American, you’ve got to recognize, I think, that the State Department and our Department of Homeland Security and our immigration folks and the FBI would be concerned. There appear to be a lot of Westerners. And as Catherine just reported, we really don’t know how many there are. And the estimates vary widely from 300-plus to 3,000-plus.

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