Each time he is given the chance, Alistair Darling insists the referendum result will be a lot closer than "people" (presumably his kind of people) like to believe.

In other words, the chairman of Better Together calculates that approaching half of the Scots likely to vote will vote Yes.

Mr Darling doesn't risk precise numbers, but you can take a stab on his behalf. There were 4.1 million people registered to vote as of December 1, 2011. Let's say there's a 75% turnout in September. Let's say that by "close" the former Chancellor means around 48% for Yes. That's 1.44 million people.

For the purposes of comparison, that's getting on for the number of constituency votes attracted by the SNP (902,915) and Labour (630,461) combined in the 2011 elections. If the September turnout is better than 75% (and that's far from impossible) we could be talking about a million and a half people. In a small country, that's a big number.

How will they feel on September 19 if a No vote has been recorded. Philosophical? Reconciled? Will they remember David Cameron's Olympic Park speech and accept that, despite it all, they are still loved and valued (and so forth) by the rest of the United Kingdom? Or will they remember the co-ordinated interventions staged by George Osborne, Ed Balls, Danny Alexander and, so it has seemed, every wing of the Westminster establishment?

The answer matters, you might think, to anyone involved in Better Together who believes in that cause. The UK contains the clue in its name. They are fighting to preserve a kingdom that must remain united, so they maintain, and in harmony, a Union founded on partnership and mutual respect. Mr Osborne seems not to have got that memo, or to have heard his leader's London speech.

"Hardball" is the macho cliche being applied to the Chancellor's fiat towards a currency union. Despite its protestations, Mr Darling's team pursues the kind of negative campaigning that never goes out of style in Westminster. No compunction is involved. The referendum must be won at all costs. But what might that cost be, exactly, if the prize is a united kingdom in the aftermath?

Mr Osborne and his fans don't seem too concerned about that. His defenders would tell you that, when he spoke in Edinburgh, the Chancellor was simply describing the remaining UK's attitude towards the emergence of a foreign country in the event of a Yes vote. For many of those who have made that choice, it sounded as though Scotland is already pretty foreign to the alleged master strategist of the Tory party. This, it seems, is a place to be put in its place.

Some Scottish Labour voters must have had similar thoughts as a dutiful Mr Balls spoke his lines for his walk-on part. Is signing up with Mr Osborne, architect of austerity, to be the price of a No vote? If their inclination is Yes, is the Shadow Chancellor really asking them to choose, in such a circumstance, between their party and their national community? Scotland's place on the Labour leadership's list of priorities has slipped, it seems, even if the price is the Labour vote in these parts. Messrs Osborne, Darling, Balls and the rest cannot be oblivious to any of this. Mr Cameron's speech was intended explicitly to advance an idea of a UK worth preserving. But the campaign to preserve the Union risks causing damage - is already causing damage - to that Union. A voter is therefore entitled to wonder on whose behalf the battle is really being fought. If the vote is No, one million and a half people will draw their own conclusions.

You could say, in fairness, that much the same reaction will be evident if a majority choose independence. This is not the sort of argument in which elevated thoughts of the democratic will hold sway for long. For a great many in the Unionist camp a Yes vote would be accepted but remain in essence unacceptable, unbearable, even traumatic. To put it no higher, Mr Osborne and his kind aren't helping Scotland or the UK. Divide and conquer is not a pretty tactic.

Perhaps that's inevitable. Predictions that the contest would become ugly have been made in this column and elsewhere for long enough. Mr Osborne didn't get where he is today, in any case, by being loveable. Party politicians can't help themselves: if frightening voters does the trick, Hallowe'en masks will be worn. But in this instance Unionism's leaders are being short-sighted in the extreme. If they succeed, they will face deep problems of their own making.

The latest release from ScotCen's Scottish Social Attitudes survey reminds us yet again that so-called devo max (the option on which we were denied a vote) remains the most popular choice for the electorate.

There's not much in it: the repatriation of all powers short of control over defence and foreign policy has 32% support against 31% for independence. Strictly limited devolution attracts the approval of just 25%.

Bear in mind that these figures are from a survey that concluded last October, long before Mr Osborne decided to lay down the law. Bear in mind, too, that, when given the straight choice between devo-max and independence or the status quo, around two-thirds of respondents preferred maximal devolution. Above all, bear in mind that the Tories and Labour still cannot say what, if anything, they would offer in exchange for a No vote.

How might opinion shift if those parties fail to match the wishes of an overwhelming majority? In which direction are voters likely to move if they are given another taste of "like it or lump it" from Mr Osborne and Mr Balls before September? The Chancellor has not sounded like a man ready to surrender fiscal autonomy. His shadow is meanwhile the leader of a party whose Scottish wing is divided utterly over the devolving of income tax powers.

Let's say these two and their allies win their No vote. Let's then accept the portents: the clearly expressed majority wish for a parliament in control of everything except foreign policy and defence is going to be denied. So how is Westminster's Scottish problem thereby solved? After the threats and menaces over the currency, cheerful acceptance is unlikely to be the mood of the majority.

At this rate, it won't come to that. Mr Osborne and his friends have already demonstrated what they think of Scotland and, moreover, of unity within these islands. Their interventions over the currency were intended as a demonstration of power and an assertion of their guiding principle. A little local devolution is fine as long as there is no challenge to their authority. For them, Westminster must prevail even if - especially if - the constitutional status quo is rejected by the people.

It's an old story, but such is the central paradox of the No campaign. If it succeeds Scotland will be left with new discontents to contemplate for a long time to come. The UK will be in a worse mess than ever before. Mr Osborne is quite the tactician.