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Donald Trump doubled down on his harsh critique of the Iraq War, saying in an interview with Greta Van Susteren that it was "one of the great bad decisions of all time" and perhaps "the worst decision ever made in the history of our country."

Trump said the war destabilized the Middle East, cost thousands of lives and left the U.S. in worse shape than it was before the war. He said that two trillions of dollars spent on the war could have been used for the nation's "dying" infrastructure.

"All of the problems that we have now stem from going into Iraq," he said.

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Greta Van Susteren asked Trump about a 2002 radio interview in which he voiced some support for going to war. "Yeah, I guess so," Trump had said when asked if the U.S. should invade.

In tonight's interview, Trump said that several months later, after he "had a chance to think about it," he decided he was against it.

He said things would have been had Saddam Hussein lived, because the deposed dictator was "very good at killing terrorists." 

"Had our presidents gone to the beach and relaxed and gone swimming, we would have been better off. We're lower now than we were when we started the war in Iraq."

Watch the full interview below.

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