And so in recent years, more often than not, human flesh searches have been associated with rising ultranationalism in China. Vigilantes today dig through people’s comments online for any sign of unpatriotic sins. Today, in addition to renrou sousuo, we have another creepy term for these activities: “ba pi,” which literally means “to skin,” that is, to expose.

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One of the most high-profile cases of this unfolded in the summer of 2017, when Yang Shuping, a University of Maryland student from China, delivered a graduation speech in which she drew a parallel between China’s air pollution and its restrictions on free speech.

She was immediately a target of renrou sousuo: The state-owned media depicted her as an unpatriotic traitor belittling the homeland, while angry netizens spread everything they could find out about her, including the address of her family back in China. Death threats were made on social media, and there were rumors, difficult to confirm, that some social media users even paid a visit to her parents’ home. Ms. Yang eventually apologized and deleted all her posts on Weibo, the Chinese equivalent of Twitter.

More recently, a victim of the Ethiopian Airlines crash in March, a young Chinese woman, unexpectedly became a target. The animosity toward her after her tragic death appears to have been prompted by a combination of nationalism and class resentment: Photos she’d posted showed that she was probably from a well-to-do family, and there were rumors that she’d had a foreign boyfriend.

Social media users dug up her Weibo account, worked out what school she’d attended and spread around old pictures. “When I see you staying in a hotel that costs thousands of yuan a night, eating fancy food, and that you can afford to fly to Kenya when you want to see giraffes, even though I won’t say I’m happy for your demise, I definitely do not have sympathy for you,” one commenter wrote. Another said, “Our country isn’t vast enough for you to spend vacation time in?”

I am not arguing that all those targeted have been innocent. There have been occasions during which the tens of thousands of internet users who have mobilized to “right wrongs” were fueled by legitimate motives. Yet whether the questionable behavior concerns fortune flaunting, supposedly unpatriotic political views or expensive vacations, society needs to consider how much public harassment or privacy invasion, if any, is justified.