This is no mean accomplishment, but the real fuss is yet to start. That will come when qualified majority voting is sought to replace members' individual vetoes, and reform of the Common Agricultural Policy (attempted). A veto is bad enough in a 15-country grouping. It is guaranteed to deadlock a widely disparate 27-member EU. As for the CAP, this goes to the very heart of why countries of the east see so much benefit in joining. This outlandish system of agricultural subsidies now gobbles half the EU budget. When poor new entrants like Poland with large farming populations press their claim, the EU budget will go into a spin if not resolved.

Yet, big as they are, these are still mundane issues if the European project is viewed in its entirety. The reason why full-scale European expansion is hardly assured of success is rooted in long European history. It is a story that makes the accomplishment of a common market and currency look like child's play. The benefits of the common market are obvious to all; whereas political union benefits a central and eastern Europe nervous of Russia but is bound to be resented in Western Europe. Europe is a continent that has historically been at war with itself, not least in the century just ended.

True, France and Germany have been able to live together after being enemies through the Franco-Prussian war of 1870 to the world wars. So the states of Eastern Europe as cold war enemies could still conceivably be taken into the fold with positive results. But their level of economic development is bound to feed through politically, with mounds of historical baggage to boot. If, in spite of a mere 40-year separation and a shared history and culture, the German reunification is yet to be termed a success, imagine the strains on an EU-wide scale where poor new entrants bring a long history of wars without the national or cultural glue.