Take a Euro banknote and challenge friends to find part of South America in the map that is on the reverse. Some will straightaway point to the three little boxes in the bottom left-hand corner of the map, the French overseas territories that include French Guiana; others will be baffled at the idea that any part of the South American continent might be found attached to a map of Europe.

It seems odd in the Twenty-First Century that the old colonial powers of the Nineteenth Century should still retain possessions in remote and unlikely corners of the world. Perhaps there are strategic interests in the retention of some, but in others, one might wonder at what motivates their retention.  Maybe it’s just the case that they have for so long been attached to a distant motherland that they would simply be unviable if they were left to their own devices.

The tie of the French territories to Metropolitan France is particularly strong, they are administered as French departments, with the French legal system and French services. Members of the French police force can find themselves serving in locations thousands of miles from their previous posting.

What seems odd about colonial outposts is the extent to which they replicate the country to which they are attached, as if divergence might threaten their status. Identity seems important to the retention of connection.

Perhaps it is a lesson that unionists in Northern Ireland could learn. There is little perceptible concern among English voters as to whether Northern Ireland remains within the United Kingdom after Brexit; it is a lack of concern borne from the perception that Northern Ireland is somewhere different. Unionists have reinforced that perception by their dogged refusal to accept socially progressive legislation accepted as reflecting British values. Living in Northern Ireland from 1983 until 1999, visits to England always seemed a journey to a country thoroughly other than the six county province in which I lived. Even with the British high street stores on the streets of Northern Ireland towns, there is still an unmistakable sense of being somewhere that was not British in the way most British people would perceive that word.

Perhaps the unionists need to learn from those French overseas territories on the back of the Euro notes, to emphasise how similar they are to the English voters who might determine their future. The current approach is only going to take them off the map of the United Kingdom.