BALOCHISTAN PROVINCE, PAKISTAN – The 22-year-old doesn't look like the traditional turbaned Taliban commander. His black hair shoots out at all angles from beneath a red cap. He smiles easily and has a neatly trimmed beard. But Hilal says he is the co-leader of 200 Taliban fighters who operate across the border in Afghanistan. "Two years ago, we only attacked Afghan officials, but now we have so many Talibs that we can attack Americans," he boasts. In a rare interview with a Western reporter, Hilal and three other Afghan Taliban fighters describe how they slip into Afghanistan, attack NATO and...