Rep. Peter King: Latest Beheading Shows US Must 'Crush' ISIS

The beheading of American journalist Steven Sotloff demonstrates that the terror group Islamic State (ISIS) cannot be negotiated with and should instead be wiped out, says Rep. Peter King.

"This is absolutely disgraceful. It's horrific. It shows how barbaric ISIS is," the New York Republican said Tuesday on CNN's "The Lead with Jake Tapper." The United States and its allies must make every effort "to crush them and destroy them," King said.

King said ISIS had made a declaration of war against the United States two weeks ago when it beheaded journalist James Foley, and that he believes President Barack Obama has the constitutional authority to strike at ISIS without congressional approval.

Unlike the beheading of journalist Daniel Pearl in 2002, Sotloff's killer did not make mention that his victim was Jewish. King said he believes that shows that the killing was based solely on the fact that Sotloff was an American.

It is a signal that ISIS is at war with the world that is "outside their very narrow world," King said.

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