President Xi Jinping says China deserves to be treated as a great power, but on Wednesday his country expelled three Wall Street Journal reporters over a headline. Yes, a headline. Or at least that was the official justification. The truth is that Beijing’s rulers are punishing our reporters so they can change the subject from the Chinese public’s anger about the government’s management of the coronavirus scourge.

“China Is the Real Sick Man of Asia” was the headline over Walter Russell Mead’s Feb. 3 column in the Journal....