Ai Weiwei and Frank Gehry, photographed in Los Angeles on Nov. 1, 2018. Credit: Joe Leavenworth

In 2011, Chinese authorities detained the artist Ai Weiwei at a Beijing airport, seizing his passport, laptops and hard drives from his studio and imprisoning him for 81 days without formal charges. The allegation was “economic crimes,” but many saw it as retaliation for his persistent criticism of oppressive government policies, whether investigating the names of the schoolchildren who died in the 2008 Sichuan earthquake or his 2009 documentary surrounding the kangaroo-court trial of the human rights activist Tan Zuoren....