Most people reading this have strong stomachs, so let me lay it out as baldly as I can: Much of what we loosely call the western world will not survive this century, and much of it will effectively disappear within our lifetimes, including many if not most western European countries. There’ll probably still be a geographical area on the map marked as Italy or the Netherlands— probably—just as in Istanbul there’s still a building called St. Sophia’s Cathedral. But it’s not a cathedral; it’s merely a designation for a piece of real estate. Likewise, Italy and the Netherlands will merely be designations for real estate. The challenge for those who reckon western civilization is on balance better than the alternatives is to figure out a way to save at least some parts of the west.

One obstacle to doing that is the fact that, in the typical election campaign in your advanced ind ...