Squeezed between US oligarchy and Russian and Chinese autocracy, Europe’s democracies stand out like a relic from a bygone age. The euphoria and sheepish groupthink on display at Donald Trump’s inauguration last month may well herald either a new US “golden age” or a hubristic bubble bound to burst. It is possible that China will succeed in reshaping the world in its image, or it may succumb to demographic decline and economic stagnation. Europe is not alone in being at a historic crossroads, but it is exclusively mired in pessimism, despondency and self-doubt. In 1492, as Christopher Columbus landed in…