YALTA, Crimea — "Who do you think is responsible for the war in eastern Ukraine?" asked Masha, a 17-year old student at School No. 12 in Yalta, Crimea. I paused. "Russia." A gasp went around the classroom. Masha looked at me as if I was mad. "No way," she said. Twenty students shifted in their seats with astonishment. The teacher shot me a "didn't-I-tell-you" look. It took a moment for calm to return.