Chinese nationalists incensed by the Japanese government’s decision to purchase the East China Sea islands last week took to the streets yesterday, the day that marks the 81st anniversary of Japan’s invasion of China. Soon however, demonstrators at the Japanese mission were momentarily distracted by a good opportunity to mess with their second-favorite country to hate. About 50 protesters swarmed the U.S. ambassador’s limousine like a horde of the walking dead. Refusing to let the ambassador back into the embassy, they reportedly threw “small objects” at the car and even — gasp! — ripped the tiny flag. Unfortunately for the Chinese government, number-one dissident Ai Weiwei happened to be on the scene while visiting a friend’s near-by apartment. He shot this video out the window, recording what might be the slowest moving riot ever.