It's Theresa May versus Nicola Sturgeon - and only one woman can emerge victorious 

Prime Minister Theresa May meets with First Minister Nicola Sturgeon 
Prime Minister Theresa May vs First Minister Nicola Sturgeon  Credit: Jeff J Mitchell /Getty

Neither Theresa May nor Nicola Sturgeon are high rollers. Yet both women have embarked on the gamble of their lives – and only one will win.

Brexit is perhaps the biggest risk any politician has taken in living memory. Admittedly, it was rather forced upon Mrs May by her far less cautious predecessor David Cameron. But like the hardened gambler she isn't, the Prime Minister has played double or quits by so far opting for a much harder Brexit than any of her allies would have thought possible when she walked into No 10 less than a year ago.

Scotland’s First Minister, meanwhile, came to the leadership after Alex Salmond – a man who likes a political flutter – lost his bet on independence in 2014. Having promised that vote was a once-in-a-generation event, the SNP leader now wants to risk it all once again.

Both women have their cards on the table, and the stakes couldn't be higher. Victory for one means political oblivion for the other

None of this appears to come naturally to either of these two impressive leaders.

Mrs May’s friends have long teased her about her caution bordering on indecision. “Theresa May, then again she May not,” is the oft-repeated quip. The PM is nothing if not considered, laying the groundwork meticulously for policy announcements. Her grasp of the detail in the Home Office meant she was rarely blind-sided by an unexpected development – even if it did leave her accused of being a control freak -  and the same is true in Downing Street.

But yesterday’s audacious move by Ms Sturgeon - who vowed to hold a second referendum on Scottish independence - caught her out. A more reckless politician might have responded in kind - with an equally bold response. But Mrs May retreated to her characteristic circumspection, putting off the triggering of Article 50 that we had been led to expect.

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The Government is now doing all it can to suggest the timing hasn't changed - but neither the media, nor Whitehall, nor the business people and European dignitaries who were preparing their responses are convinced.

While the First Minister upped the ante yesterday, she had, in her usual fashion, prepared studiously for the moment. Immediately after the EU referendum last June, she chose her words very carefully indeed. And she only started a “national conversation” on independence several months after the Brexit vote. Unlike her impetuous predecessor, Mr Salmond, every move she makes is considered, and the risks carefully weighed.

Now, though, both women have their cards on the table, and the stakes couldn't be higher. Victory for one means political oblivion for the other.

It's no surprise that the SNP has judged that - at this moment of greatest uncertainty - now is the right time to roll the dice again

Worse for Mrs May, it's a case of double jeopardy. She could to all intents and purposes win the argument over Brexit, but still lose the Union. In reality though, just as both leaders’ futures are entwined, so the outcome of Brexit and the fate of the Union are now inextricably linked.

The worse the Brexit negotiations go, the more emboldened many Scottish voters may become in risking quitting the UK, in the hopes of rejoining the European Union at a later date. And, like a game of poker, Mrs May really has very little idea what kind of cards she'll get to play in the negotiations. No wonder Downing Street is digging its heals in on the date of the second independence referendum.

And it's no surprise that the SNP has judged that - at this moment of greatest uncertainty for the Prime Minister as she prepares to trigger Article 50  - now is the right time to roll the dice once again. They've both redefined themselves, against their better judgement, as risk takers. But like all good gamblers, it's a calculated risk they're both taking.