AP Photo

What seems sometimes incomprehensible in the contemporary world makes perfect sense, if we pause and study a little history. In November 1918, had anyone in a starving Berlin predicted that, in twenty-two years, an ascendant Germany would control most of Europe, from the Atlantic to the Soviet border, he would have been considered unhinged. And if, in 1945, amid the ashes of the Ruhr, anyone had guessed that in sixty-five years, Germany would once more determine the future of Europe from the Atlantic to the Russian frontier, he would again have been written off as delusional. Yet today, cash-flush German Chancellor Angela Merkel holds the fate of the European Union in her palm—but in a far more secure fashion than an Adolf Hitler ever did.

Two inexplicable...