The SNP's final annual conference before Scotland's Day of Destiny, as Alex Salmond calls the independence referendum, went rather better than expected.

Aware that they risked squandering their main media showcase of the year, ministers unlocked the box marked "November White Paper" and sprung a few policy surprises on energy and the minimum wage. These measures were calibrated to attract the votes of those Scots who tell opinion polls that they would vote Yes if they were £500 better off after independence.

Well, £70 off annual fuel bills is a start, though environmental campaigners do not like the idea of taking renewable energy subsidies and stacking them on general taxation. The objective is to encourage people to use less fuel.

Moreover, it suggests that the SNP are unwilling to take on the energy companies by endorsing Labour's price freeze. It also implies higher taxation levels in Scotland. However, the proposal seems solid, progressive and relevant to Scottish conditions, where more are in fuel poverty.

Alex Salmond's bid for the votes of 400,000 Scots who earn less than the "living wage" of £7.45 an hour is also aimed at the Nationalist core - working-class voters in the central belt, hammered by inflation and wage stagnation. At present the living wage only goes to public-sector workers, which is manifestly unfair. Salmond couldn't promise to extend it right away, but he did promise a Fair Wage Commission and to raise the minimum wage annually by the rate of inflation, benefiting 70,000 workers. Businesses aren't going to like being told what to pay their workers, but again this measure passes the fairness test.

Alex Salmond named the day for the White Paper and promised that it would include a blueprint for a better nation. A Yes vote will be an "act of national self confidence, of self belief". Well, the SNP has those qualities in abundance. The party emerges confident, united and showing it hasn't lost its capacity for policy innovation. The SNP are also remarkably popular, with the latest polls showing Alex Salmond is still in landslide territory.

It is most unusual for a governing party to remain popular for two years in office, let alone six. And Salmond has taken a beating from a hostile press recently over everything from the legal advice on EU membership to booking an off-season room in Gleneagles. But it hasn't stuck. Salmond is not only the most popular party leader in Britain, he is vying with Angela Merkel as the most successful political leader in Europe.

Unfortunately, for the Nationalists, they have been unable to translate this popularity into support for independence. You could sense the frustration in Nicola Sturgeon's address as she warned Scots of the consequences of voting No. This conference saw the emergence of the SNP's answer to the unionists' Project Fear - the threat that Scots would lose their pensions, the pound, Europe etc after independence. Project McFear warns Scots that if they don't vote Yes they will lose their benefits, the Barnett Formula and a large chunk of public services as Westminster wreaks its revenge. Scots may also be thrown out of Europe if David Cameron gets his in/out referendum on British membership. We will surely hear more of this as the referendum draws near.

But Alex Salmond remained, as always, the personification of the positive, eschewing scare stories in favour of a picture of independence as the sunny uplands of devolution, where the Scottish Parliament gains powers over welfare, taxation and defence, and in so doing comes of age. Salmond revels in his popularity, and doesn't even bother to bad-mouth his opponents any more. His job is to appear utterly confident of success, irrespective of the polling evidence. And it has to be said that he does this very well.

The question is: do Scots see his party as the potential government of an independent Scotland? They certainly see the SNP as a credible government in Holyrood. Its leading politicians - Salmond, Swinney, Sturgeon - are as good as any in Westminster or Europe right now. However, the SNP's immense popularity in Scotland is partly down to the constitutional arrangements of the UK. Many Scots who vote Labour in Westminster elections vote nationalist for the Scottish Parliament because they want a combative devolution party that will keep Westminster on its toes and will not succumb - as the Scottish Labour Party appeared to do - to dictates from London. But wanting a better government in Holyrood isn't the same as wanting a different country.

The SNP is a strange phenomenon: a party that is vastly more popular than its flagship policy. A national liberation movement that says it wants to remain in union with the country it wants to leave. A government that says Scotland can only succeed economically with independence, and then says that the Scottish economy, under its leadership, has never performed better. Alex Salmond can't help himself, celebrating his government's achievements - tuition fees, the youth jobs guarantee, a £60 million package for 3000 jobs - even as he insists Scotland is being ground down by Westminster. These are the paradoxes that trouble voters when asked whether Scotland should be an independent country. It already is a country, a nation - no-one disputes that. It has a very capable governing party, of which many Scots, even on the Left, are rather proud. And Scotland has an effective working parliament. Voters still need to be persuaded to take what many regard as a leap into the unknown. They don't see how having limited powers over welfare, defence and taxation, while remaining in a social and currency union with England, will deliver the New Jerusalem.

Moreover, many Scots feel a filial obligation to England, having participated in the Union for 300 years.

So, in order to vote Yes Scots need persuaded not just that they will be protected from Tory austerity, but that independence will be economically beneficial, that they will not be leaving the UK, will not have to show passports at the border, can still watch the BBC, remain in Europe and will not incur the wrath of Westminster and the Bank of England, who will still exert significant influence on the independent Scottish economy. That is a tall order. It's not impossible. The SNP have 11 months to do it.