Some of my best friends — including my husband — are Scottish nationalists. There’s no rhyme nor reason to this; purely by chance a lot of the warmest, wittiest and most clever people of my acquaintance happen also to be members or supporters of the Scottish National Party. I enjoy their company, relish their intellect and would place absolute trust in them if I were in need of personal help.

Voting for them is a different matter altogether. When it comes to that tingly moment at the polling booth, when I savour that fleeting, dusty whiff of power, their party holds absolutely no appeal for me. Worryingly for the SNP, it seems I am not the only one. One of the lowlying issues in the campaign for the Scottish parliamentary elections, smouldering away quietly in a corner where the nationalist firefighters can’t quite quench it, is the evidence that nationalism is strikingly less popular among women than men.

It began with an ICM poll in The Scotsman last month showing that support among women voters was lagging between six and eight points behind male support, and has been followed by a number of ratings showing that the nationalists weren’t getting the support they’d like from women. In another poll the personal standing of the SNP leader, Alex Salmond, was almost 10 per cent lower among female voters than it was among men.

The phenomenon is a fascinating one. It is not new — historically the Scottish Nationalists have failed to appeal to women as much as to men — but for a party on the cusp of serious power for the first time it has gained fresh urgency. These days, the female voter, like the female consumer, is coveted for her power and influence. In an age when multimillion-pound marketing campaigns and product development hang upon the word of women alone, how peculiar it would be if something as momentous as the break-up of Britain were the responsibility of a predominantly male-dominated movement.

Nationalism and separatism, independence: worldwide these things have an inescapably masculine feel to them. One does not have to recall much of the Yugoslavian conflicts, Chechnya or even Northern Ireland to understand that the rhetoric of deunification is clothed in black leather jackets and spoken in a deep voice. The balkanisation of society, wherever and however subtly it happens, is fuelled by testosterone. Mostly this is symbolised by angry young men, freedom fighters, flag-wavers, stone-throwers, plotters against neighbours; in other instances it is more sophisticated and wears a suit. But nationalism is invariably a dark and macho business. Change on a scale that alters boundaries is rarely the work of women.

Quite why this is so must be open to debate, but there are obvious conclusions to be made about stereotypical roles: male aggression and female nurturing. We can play at armchair psychology all day, but it seems indisputable that most women don’t start wars of independence, however benign, because they’re too busy trying to run a peaceful home and bring up children in a stable environment. Continuity, stability, freedom from conflict: these are feminine urges and always have been. Women prefer correspondingly calm, sensible politics.

Thus the cultured Scottish Nationalists have never worried me. I’m quite impressed by some of their policies, which are largely calm and sensible. But what genuinely scares me about the prospect of any break-up of Britain is the door it will open for lager-lout nationalism — the bigoted and the boorish in Scottish society. This is a door that I’m really not sure the SNP leaders will be able to shut again (though they will undoubtedly try hard to).

You will have heard the bigots, as I have for years now. The football supporters, with their chant of “If you hate the ******* English clap your hands”. The Scots drunk who wants, over and over again, to punch someone because he sounds English (never underestimate the potency of the wrong accent in the hearing of a Scot). The small-minded, who can spoil a holiday for English people with their incivility in bars and restaurants. The cheap jibe, the golf club put-down: “What’s he like?” “He’s English”. This is gang mentality writ large: if you’re Scots you’re in our gang and must despise the English. And gangs, I need hardly point out, are male things.

This kind of blokish bigotry runs like a shallow seam beneath the surface of Scottish life. One never has to dig too deep to find it. It matters not to these people that — at risk of parroting both David Cameron and Gordon Brown in their defence of Britishness — up to half of Scots have relatives living in England and at least 400,000 English live in Scotland, by far the largest immigrant group north of the Border. Scots will happily insult the English in a way that they wouldn’t dream of insulting asylum-seekers or Poles; research by the Institute of Governance at the University of Edinburgh showed that a majority (54 per cent) of Scots would not regard an English-born Scottish resident as Scottish, but 70 per cent would bestow the privilege on a nonwhite Scottish resident.

It is hard to believe that the worst kind of saltire-wavers, ignorant of the dense weave of inward and outward migration, of the commerce and culture that has linked Scotland to England for 300 years, wouldn’t feel liberated by independence. Maybe I’m wrong. I hope I am. But my fear is that if the Scottish Nationalists do well in the election there is a danger — I shall put it no stronger — that the climate would change for the worse, allowing antiEnglish sentiment to flourish. What a tragedy that would be. For both countries.

To give it credit, the SNP is working hard to feminise its appeal. It has softened its harsh yellow and black colours; its manifesto, released on Thursday, devoted considerable weight to childcare, nursery education and primary school class sizes. The SNP’s deputy leader, Nicola Sturgeon, a smart, feisty young woman with a likeable manner, is a good perfomer. She needs to be. She has generations of macho male culture to outweigh.

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