During the 2015 general election, some Labour figures complained that there seemed to be an unholy (and entirely unofficial) alliance between the Conservatives, the ‘party of the Union’, and the SNP.

Then they were referring to the Tories’ breakthrough election gambit of warning voters in England and Wales that Ed Miliband would be propped up by the Scottish Nationalists – a tactic they look set to repeat, if the Prime Minister’s speech of yesterday is any indication.

For Scottish Labour, this never ended. Scottish politics has continued to revolve ever more tightly around the constitution, with the Conservatives and SNP profiting as the clearest advocates of either side.

So it’s not a surprise to see the Scotsman reporting that both Theresa May and Nicola Sturgeon intend to put the question of another independence referendum front-and-centre in their election campaigns north of the border.

In fact, this election is the latest indication that the Prime Minister is pursuing the most muscular, confrontational, and possibly riskiest (or at least, least risk-averse) unionist strategy since John Major’s. It will likely draw criticism from the devolutionary classes of Edinburgh, Cardiff, and Belfast alike – but those bubbles are not their nations.

It may go horribly wrong. It’s hard, however, to see that May can be blamed for trying. After 20 years it’s plain that the “more powers!” strategy of buying the nationalists off year-by-year hasn’t stabilised the constitution, bolstered Britain, or even improved the quality of administration.

That so many unionists can only prescribe more of the same, with no clear case for why it’ll be different this time, is testament to the intellectual inertia that has set in since 1999.

For good or ill, May seems to have snapped out of it. In fact, in an op-ed for the Scotsman she’s even done the unthinkable and championed Westminster:

“This will be a United Kingdom General Election to elect representatives to our UK Parliament in Westminster. That institution is of huge importance to every part of our Union. Unique in containing representatives of every community in each of the four nations of our kingdom, it is the democratic embodiment of our Union of nations and people.”

There’s less consensus on how this will play out. Alex Massie strikes a pessimistic stance in the Spectator, arguing that calling an election puts paid to the Government’s “now is not the time” tactic for delaying a second independence referendum.

For what it’s worth, this isn’t clear: a general election and an independence referendum are very different votes, and the rationale that Scots should see the post-Brexit world that Scotland will inhabit before they choose now to navigate it is still sound.

It may be that the apparent double standard finally sparks the outrage-fuelled nationalist surge that pessimistic unionist-Remainers have been predicting continually for the last year, but given that most Scots still quite clearly don’t want a vote that seems a stretch.

Kenny Farquharson, perhaps surprisingly, paints a more optimistic picture for unionists, highlighting some of the challenges facing the SNP, not least of which is drawing even with their astonishing 2015 performance. Iain Martin sets out the thesis at greater length on Reaction.

That the Nationalists will win the Scottish election very handsomely is no in doubt, but as Massie’s own readers will remember results are about perceived momentum as well as raw numbers. The SNP did very well in the 2016 Scottish elections, after all, but fell back from their previous high whilst a Tory surge became the story of the night.

How will the Tories do? Ruth Davidson’s statement was bullish, and she will almost certainly have been consulted before May made the decision to call a vote. Assuming that David Mundell can see off an SNP-Green pact in his constituency it seems probable there will be more Conservative MPs in Scotland than at present.

What’s harder to judge is how many more. This map, which purports to show what would happen under unsourced “current projections”, is almost certainly over-stating things but nicely illustrates the areas where the Tories may pick up seats: the Borders and the North East, plus the special case of East Renfrewshire.

This site will probably do a proper battleground survey before the election, but for now seats to watch include Berwickshire, Roxburgh, and Selkirk, where the SNP majority over the Tories was just 328 votes in 2015, and West Aberdeenshire and Kincardine, which was a Conservative target last time.

Although the SNP majority is solid Moray may be interesting too: not only is it home to Angus Robertson (the SNP’s Westminster leader) but also came within a hair’s breadth of voting Leave. The Tories slashed the Nationalist majority in its counterpart seat in the 2016 Holyrood elections as well. Such a scalp would put a big dent in the Nationalist narrative.