Everyone assumed it would be the threat (or the reality) of international terrorism that would ultimately break Europe’s resolve when it came to goodwill towards Mid-East refugees. Indeed, we remember vividly when the first reports of a “Kalashnikov assault” on cafes in the French capital hit social media on that fateful Friday in November. “That’s it,” we assumed, for Europe’s experiment with an open-door migrant policy. In spite of the violence and in spite of the chaos that ensued (manhunts across France, lockdowns in Molenbeek, a shootout in Saint-Deni) Europe largely kept its arms open to refugees from Syria, Afghanistan,...