As thousands fled Kyiv in the first days of Russia’s 2022 invasion, one 57-year-old grandmother hurried in the opposite direction. Liudmyla Menyuk was going to sign up for the army to avenge her son who’d been killed fighting the Russians almost a decade before. Many Ukrainians of Menyuk’s age have volunteered, sometimes motivated — like she was — by the explicit wish to stand in for a youth who might otherwise die in their place. “I performed my duties well,” she told Bloomberg in an interview, “so I could save the life of a young Ukrainian.” But the enthusiasm of...
