Bill O'Reilly got into a shouting match with rapper Lupe Fiasco about terrorism and the war in Afghanistan on his Monday show.

Fiasco was on to defend his comment that President Obama and the U.S. government are the "biggest" terrorists in the world.

O'Reilly took Fiasco to task for the comments. "President Obama is not a terrorist," he said. "He's trying to do what he believes is the right thing to do."

Fiasco tried to explain that "every president before and after" Obama could also be described as a terrorist, because of American foreign policy. "If you're going to fight terrorism, to me, you fight the root causes of terrorism," he said.

O'Reilly sternly told Fiasco that his followers "are not exactly political science PhD's" and that he was misleading them. "I don't think that that matters," Fiasco said. "I don't think that politics are as complex as people like to make them seem."

The two then started arguing about the war in Afghanistan. Fiasco said that the war had been misguided since it had strayed from its original aims.

"Why are we in Afghanistan if it wasn't to hunt down Al Qaeda and the terrorist network?" he asked.

"You are oversimplifying a message that is not true," O'Reilly shot back.

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