Even as it celebrates a mighty triumph, the Conservative Party should recognise that its election success comes laced with danger. Boris Johnson has won a tremendous victory — but only in England and Wales.

Scotland is a different matter and, increasingly, a different country too. He now faces a constitutional impasse that may yet become a crisis, the resolution of which will go a long way towards determining the success or failure of his time in office.

Delivering Brexit is one thing; ensuring that he is not the last prime minister of the United Kingdom of Great Britain and Northern Ireland quite another. Johnson has spoken about One Nation Conservatism but Scotland will be the testing ground for the seriousness and credibility of that commitment.