The migration crisis enveloping Europe and much of the Middle East today is one of the worst humanitarian disasters since the 1940s. Millions of desperate people are on the march: Sunni refugees driven out by the barbarity of the Assad regime in Syria, Christians and Yazidis fleeing the pornographic violence of Islamic State, millions more of all faiths and no faith fleeing poverty and oppression without end. Parents are entrusting their lives and the lives of their young children to rickety boats and unscrupulous criminal syndicates along the Mediterranean coast, professionals and business people are giving up their...