The dreich day in November destined to go down in history

But the media, domestic and international, will not command many votes in Scotland's referendum next September. The majority among them could complain that Scotland's Future, the 670-page White Paper on independence, is full of too-confident assertions and unsubstantiated predictions. They could ask for their "cast-iron guarantees" of the consequences of decisions to be made in a world decades hence. Yesterday, the attempt to rain on Mr Salmond's parade was fruitless.

If self-confidence earned votes, the First Minister and his deputy, Nicola Sturgeon, would have settled the referendum issue long ago. They were not so much sure of themselves as serene. They behaved as though the SNP's prospectus is a document so reasonable, so full of simple common sense, that it cannot possibly fail to convince reasonable people. But they also had the air of two politicians who believe with utter conviction that history has prepared their moment.

The difference between these Nationalists and their Unionist opponents is obvious enough. The appeal of Yes trumps the dismal word No in most human circustances. A belief in "the powers of independence to transform our country", as Ms Sturgeon put it, is always liable to be more inspiring than a witless scare story over the future of BBC soap operas. If Mr Salmond is Unionism's devil incarnate, there is little doubt that he has most of the best tunes.

Nevertheless, yesterday's launch of Scotland's Future was historic less for the policies offered than for what the very existence of the document presaged. It was not the full story of independence - Yes is a broader church by far than the SNP - nor was it likely to end the relentless quibbling from Better Together. But history will say that here was where the argument properly began, at the Glasgow Science Centre on a dark, drizzling day. Here Mr Salmond put (most of) his cards on the table.

Within the White Paper there are 650 questions and 650 answers on independence as the SNP understands the word. The answers will not satisfy everyone in every particular. The Unionist camp can be relied upon to reject the prospectus wholesale after just a cursory glance (if that). But anyone who still feels the need for more information now has 170,000 words with which to contend. Scotland's Future is a straightforward challenge to Better Together. Beat that, it says.

If you adopt the SNP's perspective, the White Paper's launch is about as historic as it gets. The elected Government of a continuing nation has set out its claim to be regarded as other nations are regarded. It has embarked on what Mr Salmond believes is an unprecedented public consultation exercise. At its heart, proponents argue, is a chance to remake our very society, to do better in terms of prosperity and justice, above all to enshrine the simple right to self-determination. That kind of thing doesn't happen every year.

Unionism's counter-arguments are less high-flown, to put it mildly. The appeal, time and again, is to your wallet and your purse. The SNP's White Paper tries to come to terms with the economic argument, insisting that no-one will be worse off thanks to independence. But fear, uncertainty and Better Together's addiction to whataboutery - the fate of sterling is this week's favourite - renders every argument vulnerable.

There is also a tendency to forget that Yes Scotland is not simply an SNP vehicle, that the White Paper does not represent all those who otherwise support independence. Many of those who will vote Yes next year will do so despite Mr Salmond's attachment to sterling, Nato and the monarchy, not because he persists with his peculiar definition of self-determination. Members of the international press might have been forgiven for missing this nuance. The First Minister certainly made little effort to enlighten them.

Ironically, the launch probably did as much for the education of our friends in the south and abroad as it did for locals. It was striking, in fact, to hear members of the Westminster press corps attempting to trip Mr Salmond up with questions that seemed, to the rest of us, like independence for beginners. That said, the widespread attention paid to the SNP document might mean that English opinion, in particular, will begin finally to adjust to the reality of the referendum and its possible consequences. In England, too often, ignorance and a kind of resentful chauvinism prevail. The effect has been to distort a debate that should matter to all the people of these islands.

A sensible person would hesitate before describing Mr Salmond and his programme as uniformly left wing, despite the claims of his opponents. He remains just as eager to cut corporation tax as the Tories or - despite their propaganda - Labour. He wants his competitive and dynamic business environment just as much as he wants social justice. The tension between Mr Salmond, the economic conservative, and Mr Salmond, the semi-leftist, gives a peculiar flavour to Scotland's Future. It often feels, in fact, like a document born of one man's personality rather than a coherent ideology.

Again, however, history might have its pennyworth to add. The Westminster parties are busily preparing themselves for the 2015 General Election. Labour leads in the polls, but the lead seems fragile. The intensifying referendum campaign coincides with a growing belief that David Cameron might yet take power without Liberal Democrat aid. That will certainly impinge on Scottish opinion.

For English voters, meanwhile, there is the sight of a hitherto overlooked Scottish party issuing a 670-page tome dedicated to the belief that there is an alternative to the Westminster consensus. Once they are no longer deceived by hokum over public spending, people in England will ask why Scotland is different. Then they will hear that favourite SNP word: choice. Mr Salmond, with little interest in influence at Westminster, could become influential indeed.

His opponents will pick away at every sentence on every page of the big White Paper. The rational demand for detail and explanations will once again become a relentless game of spot the question that no-one could answer. But Unionism, having expended much of its ammunition early in the campaign, risks a collision with simple reality. For better or worse, the SNP has tried to give 650 answers to 650 questions, but there is one fundamental question that won't go away. Why do so many nations manage independence with no fuss and little argument yet Scotland, alone on the planet, cannot hope to master the feat?

The question has nothing to do with whether one favours Yes or No. It says nothing about your attitudes to the United Kingdom. Why is Scotland held to be irredeemably different as to render a simple constitutional arrangement impossible? In one sense, all those pages produced by the Government are a reminder that other countries have already met all the challenges and solved the problems.

If the SNP launch counted as historic it was probably because it took us, finally, to that point. The arguments became real and the question of Scotland and impossible hopes began to be answered. As Mr Salmond remarked yesterday, dozens of countries have become independent since the end of the Second World War. Some have managed better than others, but none behaved as though it had embarked on a lethally dangerous journey without precedent in human affairs.

That was part of Mr Salmond's purpose yesterday. He tried to present a case that was both romantic and practical while stifling the notion that there is something inherently outlandish about independence for Scotland, alone among nations. The statement that the White Paper is "the most detailed blueprint that any people have ever been offered anywhere in the world" is a claim open to debate. The fact that Scots have a chance to consider their future like other nations is beyond doubt. One dreich November day will be remembered.