The fear and outrage that is spreading in Hong Kong is feeding anti-Communist and separatist sentiments there. This should worry Beijing, and so should the condemnation it has received from Western governments. (Mr. Gui is a naturalized Swedish citizen, and Mr. Lee holds a British passport.) But the fallout was also so predictable that one wonders how China’s leaders, supposedly grandmasters of strategic machination, went about this political calculus.The Chinese government’s questionable management of its financial markets recently has already suggested that it is seriously disconnected from reality. And now it is using brute force to snuff out a tiny Hong Kong publisher of two-bit political gossip. Is the Communist Party simply becoming more ruthless in quashing dissenting voices, or is its political judgment slipping?