Not so long ago, Eurosceptics (remember that term?) used to tell us the European Union was not what the British people had “signed up” for when they backed the UK’s continued membership of the European Economic Community in a referendum in 1975. They argued that the Maastricht Treaty of 1992 so fundamentally altered the institution that the United Kingdom had joined in 1973, that the British people ought to be consulted in a referendum, the precedent for which had been set in 1975.
The Eurosceptics finally got their referendum and Brexit is the result. Brexit was not what the people of Scotland voted for in the summer of 2016. Brexit fundamentally altered the United Kingdom in which Scotland opted to remain in 2014. The precedent having been set, the people of Scotland must be asked, in a referendum, whether or not they accept any Brexit deal, and if not, do they then wish to remain a part of the United Kingdom.