DETROIT (WWJ) – Are the threats by ISIS to kill more Americans just empty threats? Dr. Fred Pearson – Director of the Center for Peace and Conflict Studies at Wayne State University – says unfortunately, he believes the threat is quite real.

“They have obviously demonstrated their willingness, now evidently on two occasions, …,” said Pearson. “We knew this second journalist and that he was under threat of also decapitation if the U.S. did not stop – the Obama administration is not letting that stop them so this is the next step.”

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He says that terrorist groups use this method for shock value.

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ISIS, which has taken over a third of Syria and Iraq, has terrorized rivals and civilians alike with widely publicized brutality as it seeks to expand a proto-state it has carved out on both sides of the border.

“There are two types of use of force; one is for objectives and one is for pain. The pain method is often the one used by those that don’t have the full military array – it’s meant to get attention and cause cost to the opponent and make it hurt and that’s what they’ve done here, unfortunately.”

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Pearson calls it a classic hostage situation. He says there’s been a long political tradition of be-headings — which includes the French Revolution in the 18th Century, as well as in the 1950’s in Iraq.