When Volodymyr Zelenskyy became the president of Ukraine in 2019, it made headlines around the world. That wasn’t because he was a political heavyweight deemed ready to resolve Ukraine’s deep-seated challenges —ranging from an economic crisis to corruption and an entrenched, powerful oligarchy — not to mention the conflict between Ukrainian forces and pro-Russian separatists in the east of the country. It was just the opposite. Zelenskyy was a political novice whose closest brush with politics was playing the role of Ukrainian president in a well-known domestic TV series, before life imitated art and he decided to launch his own...