In Hong Kong, a teenager, Tony Chung, was this week sentenced to four months in prison for insulting China's flag. Chung also faces a trial for secession, which carries much longer sentences. On the mainland, journalist Zhang Zhan was given a multiyear prison sentence for reporting on the Communist Party's failure to contain the coronavirus outbreak in Wuhan city. Beijing says that Zhang's reporting was designed only to sow distrust in the party, but the truth of the matter is quite different. Zhang's ultimate sin was to have embarrassed Xi Jinping and...