'Changed, changed utterly" was Alex Salmond's verdict, ­echoing WB Yeats on the referendum's impact on Scotland. 

But how much really did change in those hectic September days? 

Some argue that the referendum was largely an exercise in internet hype and that very little has fundamentally altered.  After Christmas, Labour will get its act together under a new leader, and the implementation of the Smith report will satisfy demands for autonomy.  After all, the No campaign won convincingly, didn't it? 

Yes - but it was a strange kind of victory that left the losers dominating the political landscape. 

In my new book I argue that this country has emerged from the referendum experience very much changed.  Scotland now has, for the first time in modern history, a serious independence movement.  This may sound puzzling to those who believed the SNP had been an important part of the political landscape at least since the 1960s.  But a movement is more than a party, and anyway, the SNP was, despite the spike in its appeal in the 1970s, only a marginal ­political force until the creation of the Scottish Parliament. 

Today, it is the driving force in Scottish ­politics and finally in sight of replacing Labour as the national party of Scotland.  The SNP lost the referendum but won the aftermath, with recent YouGov polls indicating a 20% lead over Labour in Westminster voting intentions. 

The SNP are well on the way to ­achieving Nicola Sturgeon's target of 100,000 SNP members.  If they contribute the recommended £5 a month membership fee, this could be worth up to £6 million a year. 

This is a remarkable financial turnaround for a party that, only a decade or so ago, reportedly had to sell its party headquarters in Edinburgh in part to pay off a £400,000 overdraft.  It will now be able to pour money into General Election contests that it couldn't afford to fight properly in the past. 

But the independence movement is about much more than the SNP.  It now includes a new coalition of civic organisations like Common Weal, Women for Independence and the Radical Independence Campaign. 

There is a new independence-supporting newspaper, The National, and hundreds of thousands of Scottish voters who no longer trust the BBC or the mainstream press and obtain their news through web-based media like Wings over Scotland, Newsnet ­Scotland and Bella Caledonia. 

There is a strong cultural dimension to the independence movement, as exemplified by Scotland's Makar, Liz Lochhead, almost casually announcing her membership of the SNP.  Artists and writers have traditionally been rather suspicious of nationalism, following Orwell in seeing it as a philosophy of the right, by groups like National Collective were highly effective in mobilising creatives behind the independence cause. 

Activist groups across the left also turned as one towards nationalism, setting aside the traditional Marxist view of it as divisive and bourgeois.  The surge of support for Yes in working-class areas of Glasgow, Dundee and other traditional Labour areas changed minds. 

Organisations used to ­holding meetings in a pub suddenly found themselves capable of filling 3000-seat ­auditoriums.  Groups like the Scottish Socialist Party, the Green Party and many others found that in the Radical Independence Campaign they could work together for the first time.  They have effectively become recruiting sergeants for the SNP after abandoning plans for a new party of the left. 

Scottish nationalism has finally shed the faintly sinister image that has long been fostered by its Labour critics.  But the definitive manifestation of Scotland's new independence movement is the 1.6 million Scots who voted Yes in the referendum.  This was a transformative event - an unprecedented 45% of the electorate voting for independence. 

It is now clear that Better Together came perilously close to losing the referendum.  The key policy on which it was based, the rejection of a currency union, became a millstone.  By August, even a majority of No voters rejected Osborne's pound exclusion. 

The ferocity and negativity of the No campaign has also become part of Scottish folk memory, and with cause.  A review of the press coverage in my book shows that front-page stories - the ones that dominate the supermarket shelves - were running at nearly 4 to 1 in favour of the Unionist campaign. 

But this ratio fails to convey the near ­hysteria of the headlines - not just about Scotland being barred from the EU, the pound and Nato, but of cancer cures being jeopardised, families being split asunder and a Yes vote triggering another Great Depression. 

Day by day, key Scottish businesses were making clear their intention to leave.  The Yes campaign simply had no answer to all this - a consequence of the refusal of the Unionist parties even to contemplate monetary union. 

Alex Salmond's economic policy was in ruins, as demonstrated in his first disastrous debate with Alistair Darling.  Even so, many hundreds of thousands of Scots opted for the ruins, having come to see the Union as a relationship of subordination and even coercion. 

In defying the UK financial, political and media establishment, Scottish voters crossed a kind of rubicon.  The psychology of Scottish politics has been transformed as a result.  The moral basis for union eroded.  And the Smith Report is likely to become part of the problem rather than the solution. 

As Barnett subsidies are withdrawn and the deflationary impact of income tax devolution becomes apparent, this can only fuel demands for further fiscal autonomy.  The cost of financing Scotland's ageing population is being repatriated while the means of growing the economy are reserved. 

Westminster parliamentary sovereignty has been reaffirmed by the Smith Commission.  English Votes for English Laws are an attempt to undermine Labour's position in England.  These trends will continue to enhance the appeal of independence as Westminster politics becomes ever more dominated by austerity, immigration and anti-Europeanism. 

Scotland never ceased to be a nation after 1707, retaining its Kirk, education system and law.  It is now well on the way to restoring its political and economic sovereignty.  ­Independence is now surely only a matter of time. 

Disunited Kingdom - How Westminster Won A Referendum But Lost Scotland is published by Cargo Books tomorrow.  www.cargo.com.