There is a moment in a recent interview that captures the Jiang Xueqin phenomenon perfectly. Tucker Carlson — who has spent two decades interviewing presidents and prime ministers — ends a 68-minute conversation with a Beijing-based man no one had heard of until six months ago, and says, on camera: "I'm going to start to cry." The man on the other side nods, gracious and unhurried, in the way that people are when they have been telling the truth for a long time and are only now being heard.advertisementRead Full StoryThe clip went everywhere. It joined a growing library of…