Vladimir Putin’s definitive quality as president — his refusal ever to back down — helped him project Russian global power for years. But facing repeated setbacks in a catastrophic war in Ukraine, his inflexible approach is looking more like his great flaw. As Russian forces fled in disarray in Ukraine’s Kharkiv region Saturday — dressing as civilians, stealing bicycles, abandoning tons of military equipment and ammunition — Putin sounded strikingly tone deaf as he opened a giant new Ferris wheel in Moscow. “There is nothing like that in Europe,” he boasted via video-link. Within hours, the Ferris wheel had broken...