So now’s the day and now’s the hour at which, if you will forgive the mixed allusions, we may discern the beginning of the end of the beginning. Eight months of often tedious wrangling ends this afternoon as David Cameron and Alex Salmond agree some kind of “deal” to fix the terms and conditions of Scotland’s independence referendum. At long last the phoney war is coming to an end.

And not before time. There is talk of this being a historic day and, well, I suppose you can think it that if you want to. Most Scots, I hazard, simply want the warring parties to get on with things. (I fancy this sentiment is likely to be held even more strongly by Englishmen already tired of all this Caledonian wrangling.)

Still, it’s a good start to the SNP’s conference week. David Cameron slinks in to Scotland almost as though he were the leader of a foreign country already. You would not think he’s merely visiting territory for which he presently holds some responsibility. The optics – as the media handlers say – will favour Mr Salmond today. Why, there will even be signing and swapping of papers further bolstering the impression this is a meeting of equals.

That, of course, is how the SNP would like today’s meeting to be seen. How much any of this really matters is another issue entirely. I fancy it’s the sort of thing to which commentators attach too great importance. Nevertheless…

Similarly, many of the arguments have bordered on the futile. I see no good reason for depriving those 16 and 17 year old Scots who wish to vote the opportunity to do so. They will have a stake in the consequences of the outcome for rather longer than will, say, today’s crop of pensioners. Nevertheless, there is little reason to suppose the teenage vote will be decisive. Polling suggests there’s not – or not yet – an “independence generation” and, anyway, many of the blighters won’t even bother to vote.

Salmond’s more substantive “victory” is that the Scottish parliament – that is, the SNP – will set the question subject to it being approved by the Electoral Commission. As Fraser says this may make a difference though the examples of how it may do so that he cites do more to undermine the validity of referendums than of any of the actual alternatives he lists.

For what it is worth, it is possible for Do you agree Scotland should be an independent country? to be both the question the Nats desire and a reasonable one. It is, after all, the issue to be answered.

This whole process, mind you, has been a queer one. The SNP pressed for a two-question referendum even though adding a “More powers but not independence” option would, most probably doom the nationalist cause while Unionists, for their own reasons, opposed a two-question referendum that would, most probably, have secured the Union in one form or another.

I had, initially, favoured a two question poll but I can see there’s some virtue to the clarity afforded by a simpler Yes/No plebiscite. The difficulty is that it is not yet clear what a No vote actually means. It will not necessarily settle the matter, not least since the Prime Minister is on record as being open to “more powers” for Holyrood after the referendum.

That, however, is a discussion upon which he may have little influence. The next Westminster election must be held just six months or so after Scotland’s referendum. David Cameron may – just may – not win that election. Which means that at some point we will need to know what Ed Miliband thinks about Scotland too. What a happy thought that is!

A No campaign that hints at looking again at devolution but that ends with no such second (or, to be accurate, third) look actually being taken is a No campaign that opens the door to accusations of a breach of faith. That way trouble lies. It would make it possible – not certain but certainly possible – that this will not actually be a once-in-a-generation-vote and that, Quebec-style, the matter will go to a replay sooner rather than later.

That’s only one of several possibilities, of course but it is one Unionist campaigners need to consider. In this contest winning is not quite everything; it also matters how you win. (This applies to the SNP too, of course.)

All the evidence suggests Salmond and the Yes campaign have some tough sledding ahead of them. But there’s this too: just holding the referendum unavoidably makes independence more feasible and probable. Good morning Mr Overton, your window is open.

Thirty years ago a prediction we’d be having this argument at all – let alone that it would be led by a majority SNP administration in Edinburgh – would have seemed far-fetched. That is has come to this at all is one mark of Alex Salmond’s achievement.

A Battle for Britain? Yes, I suppose so. But, first, a battle for Scotland.

Tags: Alex Salmond, Devolution, Holyrood, Scotland, Scottish independence, SNP, UK politics, Unionism