The last time two powerful women were embroiled in an Anglo-Caledonian power struggle, it ended in 1587 with the Scot losing her head.

This time, according to the snap response to Nicola Sturgeon from south of the border, that’s how it started. The First Minister must have taken leave of her senses to demand another referendum now, squeals the shrilly authentic voice of English self-entitlement. She has to be either wildly irresponsible or driven by self-interest, or both, to plunge the UK’s Brexit negotiating position (whatever that might prove to be) into even more comical confusion. Surely.

That’s one way of analysing it (there is another to which we’ll come below). But if Sturgeon detonated her bombshell for maximum impact, hours before Theresa May was expected to activate Article 50, why would she have done it any other way?

This is politics – and while the Prime Minister lapsed into her most aggravatingly schoolmarmish mode to tell Sturgeon that “Politics. Is. Not. A. Game”, she knows that’s cobblers. Politics is absolutely everything, and a chunk of that is a hybrid sport mingling the complexities of grandmaster chess with the raw brutality of heavyweight boxing. This is largely why it fascinates, regardless of the dullness of most players.

Timing is crucial in all games, and in this one Sturgeon’s was gorgeous. Just as May was preparing to advance her Brexit strategy, she walked onto a scything sucker punch that left her bamboozled as she took the standing eight count.

Even making allowances for the wooziness, she then made a hideous tonal mistake. The last thing a British prime minister should do, when a first minister calls for a referendum, is treat them like a mischievous kid. Whatever politics is, that’s terrible politics.

Scottish independence: Nicola Sturgeon announces second referendum plans

Traditionally, the Scots have never much cared for being patronised by haughty Home Counties types belaboured by a powerful sense of English superiority. They didn’t like it from Thatcher in her post-Falklands reinvention as Britannia, or from David Cameron, Slayer of Unions, when he waited 2.07 seconds after the 2014 referendum result to raise the spectre of “English votes for English laws”. They won’t like it from May if she comes over all Gloriana, blackening her teeth and putting on the neck ruff to treat Sturgeon as a naughty younger cousin with foolish pretensions to being a grownup.

So the advice to the Prime Minister is to dismiss the notion that Sturgeon pulled a stunt to shore up sliding approval ratings, or distract from SNP problems with education, or strengthen her bargaining position over fishing rights in trade talks to come. Obviously these considerations may have played some part. A myriad of factors must have fed into an incendiary decision which Sturgeon must recognise as the gamble that will define her career.

But May should forget all that, and focus on the central reason for Monday’s coup de theatre. Sturgeon has always believed independence offers her country its best future. With Scotland a backseat passenger in a vehicle careering towards the cliff’s edge, she probably believes it more passionately than ever.

Now, you can agree or disagree with her there. For what incalculably little it’s worth, I agree. Were I Scottish, I would be mad for independence. I’d say sod the crude oil price, sod the Barnett formula and sod the pernicious English meme that poor wee Scotland hasn’t a prayer of making it across the road without Nanny May holding her hand.

I’d also say sod the uncertainties. With Brexit, how much more uncertain can it possibly get? And I’d certainly say sod the buffoons of Brexit – Gove, Boris, Fox, and the rest – who argued last summer that liberation from a union which restricted self-determination justified any risks, but will now counsel the Scots to keep a hold of nurse for fear of something even worse. How transparently hypocritical do these people need to get before a residue of self-respect automatically shuts their mouths?

That, sadly, is a purely rhetorical question. Within hours of Sturgeon’s announcement, the tabloids were unleashing the very scaremongering about economic calamity it found so distasteful from Remainers last summer.

SNP pressure Theresa May for 'compromise UK-wide approach' to Brexit negotiations

Anyway, as I said, we’re free to agree or not about whether Scotland’s best interests are served by independence. What no one has any right to do is condescend Nicola Sturgeon by questioning her sincerity. She is not just an outstandingly bold and smart politician, but one of conviction as well.

Perhaps eventually the Home Counties will learn to respect her for that, though I guess she’ll need to win two Wimbledons, two Olympic golds, a US Open and a Davis Cup to even come close.

For now, the auld arrogance prevails to hint that each imperious rebuke from May will nudge Scotland closer to independence. Whether or not that would be a boon for the Scots, it would be a tragedy for those in England and Wales whose appetite for a Tory one-party state has been sated by the hors d’oeuvres they are being force-fed.