A calculating and divisive move by Nicola Sturgeon

Scotland’s first minister is fully aware that London might not facilitate the referendum, and if so the Scottish nationalists will be able to play the grievance card and to foster the lie that England is a bully and determined to thwart the wishes of the Scots. Regrettably, the grievance card often plays well among nationalists of all hues.

This is also a premature call from Ms Sturgeon, coming so soon after the decisive defeat of the independence referendum in 2014 by a margin of 10%.

Brexit negotiations have not begun so the ultimate shape of a post-EU United Kingdom is unknown so it is wrong to prepare to leave the UK in advance of that outcome becoming clear.

The call for a referendum is unpleasant in a further respect: it is calculatingly divisive. A nationalist who passionately wanted to be independent but also wanted to bring as many people along with them in that journey would act in good faith and seek to persuade and charm sceptics and to avoid divisions.

It is no surprise that Sinn Fein echoed Ms Sturgeon’s announcement with its own demand for a border poll, because the republican party has a long heritage of sowing bitter division, and of behaving in a destabilising way.

This will be a difficult contest for the many people who want to keep Scotland in the UK, but it is entirely possible that the SNP will overplay its hand, in much the same way that Sinn Fein is at risk of doing now.

The cultural and economic arguments for staying part of the Union are very strong indeed for Scotland and NI (overwhelmingly so for here), and the 2014 referendum showed that people are susceptible to such reasoning.

The UK is perhaps more durable than it appears and it has been a place where millions of people of many cultures are happy to call home. The case for staying together will have to be made afresh but it is not a hard case to make.