(CNN)The leader of U.S. military efforts to fight ISIS in Iraq says the terror group came within 25 kilometers (15.5 miles) of the Baghdad airport. Offering what appeared to be previously unreported details, Gen. Martin Dempsey told ABC's "This Week" that the United States had to risk bringing in low-flying attack helicopters to keep ISIS at bay. "The tool that was immediately available was the Apache [helicopter]. The risk of operating in a hostile environment is there constantly," the chairman of the Joint Chiefs of Staff said. "You're not going to wait until they're climbing over the wall," Dempsey said. "Had [ISIS forces] overrun the Iraqi unit, it was a straight shot to the Baghdad airport. So, we're not going to let that happen."
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Joint Chiefs Chairman Gen. Martin Dempsey says ISIS almost reached Baghdad airport
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Apache helicopters were used to protect the airport, he said
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President Barack Obama has insisted he will not put U.S. forces on the ground
In Sunday's interview, @placeholder conceded that having U.S. troops on the ground, in theory, would help Iraqi forces spot ISIS targets.