It was early 1999 when, like Balboa first glimpsing the Pacific, I happened upon one of the heavily Muslim neighborhoods of Amsterdam and saw the future immediately. Taking in the sight of bearded men in long skirts and women in hijab with three or four small children apiece — and noting the hostile looks I got from the men, and the obvious and deliberate separation of the women from the society around them — I recognized at once the demographic significance of it all. Somehow, moreover, I grasped instantly that this couldn’t just be happening in Amsterdam — why would it? It only seemed logical that there must be such neighborhoods in other Western European cities, too. I had never read or heard a word about this phenomenon. But now here I was in the midst of it, and between one moment to the next my view of the city, and the continent, that I, a native New Yorker, had relocated to because I viewed it as civilized, pleasant, and safe, was utterly transformed.