The war dragged on. Kattan was nearly shot by a sniper; Halabi and his brother Yaman, who also worked as an activist, were nearly buried in an air strike on an underground hospital that was treating victims of a chemical attack. When Assad’s forces looked weak, Russia sent ground troops and fighter jets to support them. The rebel-held half of Aleppo—one of the oldest continuously inhabited cities in the world—became a bombed-out wasteland.