BEIJING—The seed of the catastrophic Third World War of 2033-2036, destined to kill some 80 percent of the planet’s population, was planted and nurtured Wednesday by Beijing middle school gym teacher Xiao Feng. “Keep striving, keep improving for the greater glory of China and her people!” Xiao shouted at the 11-to-13-year-old boys of Beijing Jingshan Middle School, a loudspeaker blaring a triumphal march as they raced around an oval track and began to slowly germinate a tiny grain of hostility that will one day bloom into massive, unprecedented human annihilation. “The decadent Western pigs are gaining on you even now!” Following the grueling two-hour training regimen, Xiao informed pudgy underperformer and future Chinese dictator Sun Cheng that he was a total failure and always would be.