In 2018, Ethiopia and the world were in the throes of "Abiymania", a fervor of popular support for the divided country's young, charismatic new prime minister. Arriving as if from nowhere, Abiy Ahmed, a Pentecostal Christian, promised democratic salvation and national unity. For his role brokering a historic peace with neighboring Eritrea, he received the 2019 Nobel Peace Prize. Hailed at home as a prophet and abroad as a liberal reformer, Abiy was...