This is the beginning of the end for Vladimir Putin regardless of Yevgeny Prigozhin’s decision to turn around last night. That may seem an odd thing to say. But Putin’s power rests on projection, on propaganda, on the image of invincibility. Now, all of a sudden, the curtain has been snatched back, revealing the Wizard of Oz as a small, mediocre, frightened man.From the outside, dictatorships can look monolithic. One of the reasons that Western Kremlinologists failed to predict the end of the Soviet Union was that they knew little of the necessarily secret rivalries within it. None of them...