French food conglomerate Danone is embroiled in a bitter dispute with a Chinese joint venture partner. The quarrel reveals just how fragile business deals in China still are today. The Chinese protestors headed straight for the Portman Ritz Carlton, a Shanghai luxury hotel. They wore yellow caps and yellow shirts, and they were carrying huge protest banners that read, in blood-red characters: "Traitors and watchdogs will come to no good," and "We want Chairman Zong. Under no circumstances do we want Danone." The spectacle was short-lived. The police quickly moved in and removed the troublemakers from the scene. But their...