In April, Ukrainian voters took a desperate gamble and elected as their president a television performer who played a humble 30-something schoolteacher, Vasyl Petrovych Holoborodko, on a show called “Servant of the People.” On the show, a rant by Mr. Holoborodko against Ukraine’s culture of corruption had gone viral, capturing the mood of a young country profoundly frustrated by the state of affairs and ready for change.

The question ever since has been whether Volodymyr Zelensky, the comedian who played Mr. Holoborodko and now leads Ukraine, is indeed the idealistic, modest and scrupulously honest corruption-buster whose guiding thought as president is: “One should act in a way that doesn’t evoke shame when looking into children’s eyes. Or their parents’. Or yours.”

The infamous reconstructed transcript of Mr. Zelensky’s telephone conversation with President Trump does evoke embarrassment. The Ukrainian enthusiastically demeans himself before Mr. Trump, calling him a “great teacher,” joining him in trashing European leaders, bad-mouthing the American ambassador Mr. Trump fired for all the wrong reasons and pledging to work on the investigations that Mr. Trump was seeking for his own political ends. He also notes that he stayed in one of Mr. Trump’s hotels the last time he was in the United States.

But whether that performance was Mr. Zelensky revealing his real self or his Holoborodko character colliding with rude reality is a tough call. Ukraine, as Mr. Zelensky has noted, is fighting two wars — one against entrenched corruption fueled by a coterie of oligarchs, the other against rebel secessionists in eastern Ukraine propped up by Russia.