Nicola Sturgeon on her journey from coastal town to the heights of power

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Media captionNicola Sturgeon takes a walk with the BBC's James Cook, telling him about her life along the way

The First Minister of Scotland Nicola Sturgeon has been talking to the BBC as part of a series looking behind the politics of the party leaders. She says people in England should not be frightened of her party, but they should expect the SNP to assert itself after the general election.

On the North Ayrshire coast - in the heart of Robert Burns country - Nicola Sturgeon is strolling on the beach in a biting wind.

The slight, smart figure in winter jacket and big black gloves might not look like a romantic radical but few things in domestic politics are as dramatic, as revolutionary or as contentious as her central aim - to repeal the 300-year-old union between Scotland and England.

Why does she want to do so?

To answer that question Ms Sturgeon, 44, turns back the clock to her formative years here where she was educated at Greenwood Academy in Irvine before reading law at the University of Glasgow.

The picture she paints of the 1980s, of dying industry and fading spirit, is almost dystopian.

"When I grew up here the Tories were in power," she says, "Margaret Thatcher was prime minister. There was a sense of real, almost hopelessness.

"You had the prospect of leaving school and maybe never getting a job."

So why, like so many other Scots, did she not turn to the Labour Party?

There is nothing to be frightened of from the SNP - wanting Scotland to be independent is not turning our back on England."

Ms Sturgeon says: "I think even back then it just seemed to me that Labour wasn't able to offer real protection against the Tories.

"For me it was: what's the point of voting Labour if you've got, I think in those days it was 50 Labour MPs, but they could do nothing to stop what Mrs Thatcher was doing?

"And that very directly is what led me to think, well why should we have governments that we don't vote for? Surely it would be better if Scotland was independent, choosing our own governments."

Pressed on why she didn't choose to fight for "social democracy" within the framework of the UK, she has a simple answer: Scotland is a nation.

In which case, I wonder, does her vision not assume something distinct in the national character of the Scots?

Doesn't all nationalism rely, to a certain extent, on a collective mindset of a nation, as distinct from that of its neighbour?

Does she, in short, think that Scotland is better than England?

English grandmother

No, she insists: "For me it's never really been about identity.

"A lot of what people associate with being British, the social and cultural and historic ties, they matter to me."

Her own grandmother, she points out, was from the north of England.

The argument for independence is purely political and economic, she insists.

Nowadays Ms Sturgeon divides her time between her home in Glasgow and Bute House, the grand official residence of the First Minister in Edinburgh's New Town but her extended family remains rooted in Ayrshire.

She seems comfortable here on the coast on a sunny morning, chatting to anyone and everyone, going out of her way to shake hands, posing for seemingly endless selfies.

Image caption Bonny baby, a wrapped up Nicola Sturgeon in her pram in 1970
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Image caption Nicola Sturgeon poses in Bute House, Edinburgh, with her official First Minister's portrait
Image caption The toddler Nicola Sturgeon would in her teenage years enter the political arena

"There's the boss" says one man simply before we head inside a cafe on the front in Irvine.

Over bacon rolls and coffee her father Robin and mother Joan show off the baby photos.

"Who would have thought she would become First Minister," her mum Joan wonders aloud.

Well, there were signs that she would tread a political path.

At the age of 16, Nicola Sturgeon - variously described as shy, studious and intense - plucked up the courage to knock on the door of the SNP's local candidate, Kay Ullrich, and offer to help with her campaign.

Ice skater

With the idealism and enthusiasm of youth, Ms Sturgeon genuinely thought they could win the seat of Cunninghame South, she recalls.

In fact Labour romped home with a majority of nearly 17,000. The SNP came fourth with just 11% of the vote.

She might have been better off spending more time at Frosty's Ice Disco which, she fondly recalls, was where she skated to '80s pop music every Saturday night.

Of course she persevered and now represents the seat of Glasgow Southside (formerly Govan) in the Scottish Parliament.

It has been a long road from Frosty's to St Andrew's House where she is the first woman to run the devolved Scottish administration since it was established in 1999.

Women, says the first female First Minister, have made a lot of progress in her lifetime "but there's a long way to go".

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She has often spoken of her ambition to create a better future for girls like her niece Harriet, who is eight.

"Unlike Mrs Thatcher I want the fact that I am in this position to change things for the better or help change things for the better for other women in all walks of life," she says.

Her image as a feminist champion might not be helped by her husband Peter Murrell, the affable chief executive of the SNP, whom she married in 2010.

"She still irons my shirts" he points out over coffee in the cafe, with a twinkle in his eye.

"Only domestic thing I do," replies his wife quickly, adding "I think in my head as long as I do that I'm off the hook for everything else."

'Wee lassie'

Of course jokes between husband and wife about who does the ironing are just that, jokes. But, as a woman in a sphere dominated for so long by men, Ms Sturgeon has been subjected to sexism masquerading as humour many times.

The most recent examples were the Sun mocking up a picture of her in a tartan bikini and, at the Scottish Labour Party conference earlier this month, the MP for Midlothian David Hamilton referring to her as "the wee lassie with a tin helmet on," a disparaging reference to Ms Sturgeon's hairstyle.

Do attacks like these hurt?

"I'm human," replies the SNP leader (who also reveals a fear of dogs during our interview on the beach) "of course any politician who says they don't get upset occasionally by things they read in the media is not being honest.

"Often it's your family that get more hurt and wounded by some of these things."

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Image caption Nicola Sturgeon and her family, including niece Harriet, posed for pictures at parliament

She does not dwell on the subject for long, preferring instead to talk about the defining event for her generation of Scottish nationalists.

A couple of days before last September's referendum on independence it was apparent that Ms Sturgeon and other senior figures in the party felt that victory was at hand.

With expectations so high, the result - 55.3% to 44.7% against secession - was crushing for the losers but the weight appears to have lifted from them remarkably quickly.

The Scottish National Party, which Ms Sturgeon has led since Alex Salmond resigned the day after the defeat, remains energised and is riding high in the polls - astonishingly high for a party whose raison d'être was decisively, if not overwhelmingly, rejected by the electorate just six months ago.

In fact the SNP, whose previous Westminster high-water mark was 11 MPs in the election of October 1974, is now forecast by some pollsters to take almost all of Scotland's 59 seats in the House of Commons.

If such extraordinary predictions prove correct there would be both opportunities and challenges for the SNP leader.

Nuclear weapons

Opportunities because her MPs could hold the balance of power if a tight election left Labour and the Conservatives short of a majority.

Challenges because the SNP's choice may be between, on the one hand, supporting a Labour Party committed to austerity (albeit at a slower pace than the Tories) and the renewal of Britain's nuclear weapons system - policies the SNP opposes - and, on the other, refusing to back Ed Miliband and being blamed north of the border for allowing David Cameron back into Downing Street.

The SNP "would never put the Tories into government" vows Ms Sturgeon but she adds "we're not going to support Labour policies that are just Tory policies in disguise either."

England shouldn't be "frightened" of the SNP, she says, but "this is an opportunity for Scotland to force a different political direction and to get more progressive politics inserted right into the heart of Westminster."

Nicola Sturgeon - a private life

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Media captionNicola Sturgeon says making independence appealing to women "will crack the referendum"
  • BBC presenter Jackie Bird, who spoke to Nicola Sturgeon, said: "She chatted to us in her kitchen which she revealed, with disarming honesty, she rarely visited. She also conceded that unless women could be persuaded to favour independence the referendum would not be won."

So why should people south of the border, if they have voted by a majority for the Tories and their policies, put up with that?

Because you wanted us to stay in the union, is Ms Sturgeon's answer, and that means we get to participate in government as equals on a pan-UK basis.

Scotland, she continues, was "told this repeatedly during the referendum - that we were an integral part of the UK, our voice was to be heard and mattered and what we thought really counted - so don't be surprised if Scotland now wants to take those Westminster politicians at their word".

The SNP, she says, is preparing "to assert ourselves" to "influence the direction that politics at Westminster takes."

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Image caption Nicola Sturgeon has been an SNP campaigner since the age of 16

This is provocative language to say the least and leaves the SNP open to the charge of hypocrisy.

The party which spent years complaining bitterly about the "democratic deficit" which "denied Scotland the government it voted for" has abandoned its stance of not voting on English-only issues and is now prepared, it seems, to enforce potentially unpopular policies on England.

It's as if, ever so politely, Ms Sturgeon is saying: this is the constitutional arrangement you wanted, let's see how you like it.

How the Tory shires react to the challenge from this "working class girl from Ayrshire", as she describes herself, may determine not just the make-up of the next government at Westminster but the future of the United Kingdom.

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