It’s just over a hundred days since the UK voted to leave the European Union, and the political world continues to turn upside down.

The Prime Minister sounds like Alex Salmond in talking of the UK as a “fully-independent, sovereign country”, fundamentalist Nationalists urge their party leader to be cautious, and Ruth Davidson suddenly has “confidence” in Boris Johnson.

But the “starting gun”, as headlines scream across the country, has undoubtedly been fired: Parliament will be asked to repeal the 1972 European Communities Act and Article 50 will be triggered by the end of March 2017. There won’t be a second referendum, nor a general election before 2020.

The SNP, true to form, has attacked the UK Government for lack of clarity. On Saturday the First Minister tweeted that news of a “Great Repeal Bill” enshrining all existing EU law simply stated “the obvious” and demanded “more detail on the nature/timing” of Brexit.

First of all I’m not sure it was “obvious”, for some Eurosceptic Tories won’t like the fact this makes it harder to undo certain EU regulations, while Ms Sturgeon got what she wanted when it comes to both the nature and timing of Brexit.

More to the point, Mrs May specifically ruled out any special deal enabling Scotland to remain in the EU. “Because we voted in the referendum as one United Kingdom,” the Prime Minister said, “we will negotiate as one United Kingdom, and we will leave the European Union as one United Kingdom. There is no opt-out from Brexit.” Her comments on immigration also suggested continued membership of the single market wasn't an option.

“PM going out of her way to say Scotland's voice and interests don’t matter,” was the First Minister’s tweeted response. “Strange approach from someone who wants to keep UK together.” But given Ms Sturgeon doesn’t care about keeping the UK together, the inescapable reality is that she now has very little excuse not to fire her own starting gun on a second independence referendum.

If the UK Government doesn’t intend to go into negotiations with the 27 other member states asking for Scotland to somehow remain within the single market or EU, then such a quixotic compromise is hardly going to emerge further down the line.

And given the SNP leader’s repeated framing of EU/single market membership as a “red line”, it’s difficult to see how she gets beyond this week’s Conservative conference without moving things on. Yesterday an SNP press release highlighted continuing “uncertainty”, but the logical response to that is to reduce that uncertainty by giving Scots a clear choice between the UK and the EU.

As I’ve written before, the First Minister can either push forward with a second referendum or fudge it, attempting to buy time until the UK formally exits the EU, perhaps in the spring of 2019. But such an approach is subject to the law of diminishing returns, although judging by yesterday’s round of media interviews the game-playing has already begun.

Interviewed on the BBC, Scotland’s “Brexit minister” Mike Russell warned that the Scottish Parliament might block the “Great Repeal Bill” given that a Legislative Consent Motion is required before Westminster can legislate on devolved matters. This revives the notion of a “Scottish veto” which, for the past few months, the Scottish Government has neither embraced nor explicitly ruled out.

Also interviewed yesterday, the Scottish Conservative leader Ruth Davidson reinforced Mrs May’s point, that the EU referendum, despite subsequent framing, had been a UK-wide vote and thus there would be “no veto for the Scottish Parliament”. The UK is the member state and foreign affairs is – according to the 1998 Scotland Act and all subsequent amendments – a matter reserved to Westminster.

Nicola Sturgeon is fond of claiming that, during the first independence referendum, Scots were repeatedly assured by senior Unionists that the UK was a “partnership of equals” and therefore the fact Scotland voted Remain had to be recognised in the forthcoming negotiations. Now it’s a superficially compelling point, but in reality those campaigning for a No vote back in 2012-14 said no such thing.

Sure, there was lots of talk about the UK being a “family of nations”, but that isn’t the same thing as arguing that Scotland and England (and indeed Wales and Northern Ireland) somehow occupy the family home on an equal basis. The only senior Unionist to use the phrase “partnership of equals” was the former prime minister Gordon Brown, but he was talking about his (unfulfilled) proposals for a quasi-federal UK rather than the status quo.

In fact the two politicians who used that phrase most frequently were Alex Salmond and Nicola Sturgeon, usually to describe how they envisaged Anglo-Scottish relations post-independence, but subsequently the line has been attributed to their opponents, so successfully that many of my Unionist chums genuinely believe that David Cameron, Nick Clegg, et al described the UK in those terms.

It’s a good example of how brilliantly the SNP frame the terms of debate by repeating out-of-context quotes ad nauseam, and also how bad Unionists are at rebutting it. But whatever the reality, such rhetoric has obvious limitations. Yesterday the Prime Minister said she would “never allow divisive Nationalists to undermine the precious Union between the four nations of our United Kingdom”, but of course by ruling out any veto she allows “divisive nationalists” to depict her as deaf to legitimate Scottish concerns.

Ms Sturgeon was quick to highlight the irony of Mrs May’s “fully-independent, sovereign country” rhetoric, again via twitter (“These pesky Nationalists, eh? Obsessed with independence!”), but as Scottish Labour’s Europe spokesman Lewis Macdonald pointed out, two rhetorical wrongs don’t make a right, the notion of undiluted sovereignty being “just as meaningless for Britain in the 21st century as it is for Scotland”.

No country, be it Brexit Britain or an independent Scotland, can ever be “fully independent”. And beyond the theoretical “equality” between sovereign nations, there will always be big states and small, more or less powerful countries. Just as Scotland can’t be “equal” to England by dint of geography, population and economics, nor can Ireland or Denmark be “equal” to Germany and France within the EU.

Yesterday the SNP’s Westminster leader Angus Robertson had a pop at Tories for indulging in “post-Empire fantasies”, and he had a point, but then Nationalists, whether British or Scottish, are prone to fantasy, it being easier to conjure up future visions of greatness rather than deal with the here and now.

But following the Prime Minister’s speech it’s now got to the point where the First Minister has to stop commentating on events via Twitter and actually say how she’s going to respond to the UK Government’s intention to take Scotland out of the EU and single market in two years’ time. She has her own conference speech in just 12 days – will she follow the logic of her own “red line” arguments or attempt to buy more time?