Constitutional clashes over devolution are just beginning

Who knows what was in Nicola Sturgeon's mind when she railroaded through the Scottish Parliament a bill allowing 16-year-olds to change their gender before the law. Maybe she decided after a period of sincere deliberation. Maybe it reflected a long-standing belief,  just possibly - it was the result of successful lobbying by an influential and vocal constituency.

- MARY DEJEVSKY

Or, of course, she could have seized on the hugely controversial issue of trans rights as a way of at once demonstrating her own progressive credentials and an opportunity to pick a new quarrel with Westminster. If so, she has been spectacularly successful and not for the first time.

Over the years, she has shown a more acute sense of politics the big picture and small -than almost anyone in political office in the UK today. Whether or not the innocently named Gender Recognition Reform Bill was a deliberate provocation, Scotland's first minister must be gratified by the frenzy she has once again stirred up in London. Opposing Westminster is a time-honoured way for the Scottish National Party to win points with its supporters, and it did not take long for the UK government, in the shape of the Scottish secretary, to announce that it was blocking the law.

The only surprise, perhaps, was that the UK government had invoked Section 35 of the Scotland Act, resorting for the first time to a provision known as the "nuclear option" rather than initiating a court challenge. Sturgeon denounced the UK's veto as "a full-frontal attack on the democratically elected Scottish parliament". But there are two important questions here that need to be separated: firstly the issue of transgender people's rights, including the right to self-identify in a new gender and at what age. . The second is the quite different constitutional question that is now in play about devolved powers.

Mixing the two is one reason for the consternation, even indignation, in Westminster; with a subtext of "how dare she march Scotland into a conflict with the UK, and on such a sensitive issue to boot?" To which the only reasonable response is to ask everyone to calm down.