Fredrik Segerfeldt makes several of the familiar arguments for European integration: It’s contributed to peace on the continent, to intra-continental trade liberalization, and to deregulation. Fine. But how much of those contributions are the result of the EU’s being a free-trade area, and how much to its being a proto-state? In other words, is there a point beyond which “European integration” becomes a bad idea? And if it’s an all-or-nothing deal, do the benefits that we have already seen justify costs that are probably going to mount in the future?