With its decision to open membership negotiations with Turkey, the European Union has taken a heroic gamble. If all were to go well, the EU would absorb a prosperous, democratic, large and overwhelmingly Muslim country. The signal this would send would be beyond price. If the conditions for entry were fudged, the EU’s most populous member would be troubled, poor and unstable. Yet if the EU were to reject Turkey unfairly, instead, it would create a dangerously embittered neighbour.

The stakes then are huge, so huge that if Turkish membership were being discussed for the first time, the EU would almost certainly reject it. In the eyes of many Europeans, Turkey is too large, too poor and too Muslim to be a successful member. But promises had been made. Rightly, therefore, the EU has proceeded to negotiation.