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They are America's finest, the Green Berets...
They're in Afghanistan right now, training the local army... Turning Afghans into professional soldiers, ready to take over when the United States pulls out.
It's tough work... out on patrol, fighting the Taleban.
But there's also a hidden danger... the risk of self-inflicted casualties.
60 Minutes spent two and a half months with these crack U.S. troops and saw how often things can go badly wrong.