That expert, Eric O'Neill, told the Daily Caller News Foundation that ISIS was testing the model he called, "small randomized attacks" when it went on a shooting and bombing spree throughout Paris, killing 129 people and wounding another 352.

"I think this was a test to see how well this could work in a city. Can we coordinate it? Can we effectively carry it out," O'Neill told the DCNF. "My sense is they are benchmarking themselves. They are going to see if this could be deployed somewhere else because if this was a test, then they passed."

The same test "could have happened in a Washington, D.C. or New York, or Los Angeles and San Francisco, yeah, easily," he said.

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