Editorial: ​A new Irish plan to destroy the United Kingdom shows how quickly the mood on the constitutional question has changed

Ireland’s deputy prime minister has said he is pushing for an all island – in other words, the destruction of the United Kingdom of Great Britain and Northern Ireland.

It is a sign of how quickly the mood on the constitutional question has changed that there is little surprise when someone in Simon Harris’s position can say this (although not so little surprise that RTE buried the story – on the contrary, the Irish national broadcaster had it at the top of their website yesterday afternoon, fuelling the impression that much of the media on either side of the border is quick to relay a sense of head of steam for change).

The Tanaiste was speaking in his role as leader of Fine Gael, so it is not quite the case that the Irish government itself is developing the new blueprint for an all island – one that he says his party will publish at its conference later this year. But even so, the fact that FG are working on such a plan when in government is itself telling – it is the party that emerged from pro treaty factions in 1921 and has historically been less anti British than Fianna Fail and slower to adopt reflexive, traditional republican stances.

A benign explanation for the new rhetoric is that Sinn Fein’s rise in the Republic has made all the main parties there commit to plans for an all island. Meanwhile, SF itself has failed to break through politically – as was apparent in two recent by-elections in the south.

But unionists can only derive so much comfort from those truths: the fact is that public feeling in the Republic has become greener since Brexit. And bolder on destroying the UK too.

Jon Burrows is right that this partly reflects frustration that support for change in NI is not as high as they want. Even so, the Tories and Reform must devise a plan for how they will withstand this Irish nationalist pressure if they form a UK government.