The SNP has been at least a decade ahead of the Conservatives when it comes to strategic thinking.  During the late 1970s and early 1980s, the radical devolution of powers to local government might have been enough to shoot the separatist party’s fox.  Instead, Margaret Thatcher tried pretending it wasn’t there.  During the late 1980s and early 1990s, a Scottish Parliament might just have headed the SNP off.  Instead, John Major eventually settled on sending back the Stone of Scone.  During the late 1990s and early 2000s, the “Vow” might have done the trick.  But by then the Party was in opposition, and preoccupied less by the Union’s problems than its own.

It is of course possible, perhaps even likely, that none of these gambits would have worked – and that a sustained “Stay With Us” campaign for the Union, making the case for it in emotional as well as economic terms, wouldn’t have worked either.  We can’t know.

What he can be sure of is that, at every step of the miserable journey to where we are now – that’s to say, to two in five Scots already voting for independence and the SNP set for a big advance in less than a month – the Conservatives have been reacting to the anti-British party (as Harry Phibbs correctly calls it) rather than working to get ahead of it.

And there is only one means left of getting ahead of Nicola Sturgeon, who has gained more impetus from last week’s TV election debate than the other party leaders, and of Alex Salmond, who is set to be the main force in the SNP’s bigger band of MPs from north of the border.  The pre-1997 constitutional settlement is dead – and, even on this day of resurrection, dreams of reviving it are nostalgia at best, self-deception at worst.  The Tony Blair/Gordon Brown devolutionary halfway house has failed, too.  It was always unfair to the other three parts of the United Kingdom in any event.

That leaves only one policy standing that might save the Union: a federal UK, as championed in the ConservativeHome Manifesto.

Sturgeon and Salmond suggest publicly that they will work to turn David Cameron out of Downing Street, if he leads a minority government in little less than a month, and put Ed Miliband in.  It follows from this that they would reject any federal offer that Cameron might (and should) make them in exchange for not bringing him down.  Certainly, they would have good reason to – since federalism is the last remaining chance of heading off SNP dominance of Scotland, at least in the short-term, and perhaps independence itself after the second referendum that Salmond and Sturgeon are working for.

Such a referendum will be hard to deny if the SNP sweeps the board in Scotland’s own elections next year.  I am not absolutely convinced that Sturgeon and Salmond would turn down such a “big, open and comprehensive” offer from Cameron (after all, the SNP wants him back in office, as Sturgeon’s conversation with the French Ambassador confirms), but we must take them at their word.

Meanwhile, Cameron and George Osborne are coming under fire in some Unionist quarters for their “Vote Miliband, Get Salmond” campaign.  This is not a criticism shared by this site.  Both are absolutely entitled to point out the logical end of Salmond and Sturgeon’s public stance.

However, posters showing Ed Miliband in Salmond’s pocket, or post-debate spin pointing out that Sturgeon did better than the Labour leader, are tactical gambits, not strategic ones.  And as matters stand on this Easter Sunday, the Conservatives – like the other two main Unionist parties – have no strategic plan to outwit the SNP at all.  By its very nature, such a plan would not stop on May 7.  It would look beyond it to maximising the Party’s own chances in the 2016 elections and heading the SNP off from a triumph that would make that second independence referendum inevitable.  There is no guarantee that the Union would win out a second time round.

This Ozby election campaign will not take the Conservatives to the 40 per cent of so of the vote that they need to become the dominant party at Westminster – the natural party of government once again.  But it is the Party’s best chance of gaining the 35 per cent or a bit above that might squeeze Cameron back into Downing Street, thereby igniting a Labour leadership crisis.  That being so, the best course is to stick to it (though there are one or two adaptations that we will turn to later this week) if the Conservatives want to maximise their chances of success.

But sticking to the course, when it comes to Scotland, means sticking to no identifiable course at all.  If you disagree, simply ask yourself: what is the Conservative policy on Scotland?  How would you sum it up a few words?  There is no convincing answer.  Cameron should therefore tear up whatever timid draft may be nestling in his in-tray, and pledge Home Rule for Scotland when the Party’s manifesto is launched next week.  Such a promise would have the added benefit of making English Votes for English Needs more credible since, in a federal UK, it would be par for the constitutional course.

We have reached a critical point in this election campaign.  Not sticking to the campaign plan risks lessening the chance of David Cameron returning to Downing Street.  But sticking to it risks increasing the chance of Scottish independence by, once again, repeating the failed ploy of tackling the SNP not with strategy, but with tactics only.  This has demonstrably failed – even in the last six months.  “Cameron can’t go on like this,” we warned six months ago, as he rushed out his offer on EVEN in the Scottish referendum’s aftermath.  But Downing Street has, with the result we see today.

This site exists, as its mission statement says, to be supportive of the Conservative Party (though also to be independent of it).  However, some things are even more important than a Tory election win, and safeguarding the Union is one of them.  Number 10 would doubtless reply that the Union can only be saved by a Conservative victory in a few weeks’ time.  But at the moment, it is hard to see how.