On the streets of Kabul last March, I saw a small figure turn a corner about 20 feet ahead, then a flash of recognition, a huge smile and a big wave. For 10 maddening minutes we stared at each other, Samir and his shy little sister Malika on one side of the barricade, I on the other — too far apart to speak, too long to keep waving like an idiot. After our first hugs, Samir said to me, “Parwana, she is dead!” I showed him the photo of Parwana — an impish little girl who sold trinkets on the street to help support her family — that I keep on my phone. His eyes filled with tears at the sight of her. “She was a good girl,” he said. “Yes,” I agreed, “a very good girl.” Last month marked one year…