Michael Sheehan, executive chairman of the Combating Terrorism Center at West Point, says ISIS is all about holding territory, which is expensive, and that support for terror attacks in the West is a lower priority, even if they grab headlines.
"I am not sure they are really achieving anything by these very infrequent one-off attacks," he said. "They are in the news for a few days and life goes on."
A U.S. counterterrorism official said that encouraging attacks by "fan boys" in Paris and Tunis allows ISIS to reap cheap publicity without expending the precious revenues needed to protect its caliphate in Iraq and Syria. All the terror attacks require, said the official, "is an idea and a hashtag."
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Oil, extortion and crime: Where ISIS gets its money
ISIS now pays its fighters—and bureaucrats—from money it stole from the Central Bank of Iraq when its fighters overran Mosul and took control of the local branch last June. Just after the raid, the governor of Nineveh Province told The New York Times that ISIS fighters emptied the vaults in all the other banks in town as well, and estimated the total take at $400 million.
An executive with the Iraqi Central Bank gave a lower figure, $85 million, and U.S. intelligence officials also said privately the number was grossly inflated. But officials now think the number should be revised. According to one analyst, the total really is in the "hundreds of millions," even if $400 million is too high.
That would make ISIS the richest Islamist terror group in history, with a significantly higher bank balance than al Qaeda prior to 9-11.