Talk about idealists being mugged by reality. If fragile Belgium does, as some are predicting, finally collapse into its Flemish and Walloon constituent parts it will amount to the biggest embarrassment for believers in a deeply integrated European Union since the Treaty of Rome first called for an “ever closer union” half a century ago.

The current crisis in the EU’s host nation has been long in the making. It was brought to a head by the failure of parties divided on ethno-linguistic lines – Dutch speakers in the north and French speakers in the south – to form a government after elections three months ago. The French-speaking Walloons still show little appetite for separation. In the Flemish north, by contrast, support for independence has widened dramatically from its base inside the far-right Vlaams Belang (Flemish Interest) party and is edging towards the 50 per cent mark. If an external or internal shock shifted the terms of debate any further in the separatists’ direction, the Kingdom of Belgium could be history.