By Peter YOUNG

Nine days ago, a poll in the run-up to this week’s referendum on independence for Scotland sent shockwaves through the political establishment in Britain. For the first time, the Yes vote in favour of independence took the lead - 51 per cent of those polled wanted to break away from the United Kingdom while 49 per cent supported the status quo. This overturned a 14-point advantage enjoyed by the No campaign as recently as the middle of last month.

The real prospect of a victory for the Yes campaign in Thursday’s vote caused immediate panic amongst the politicians at Westminster. As a result, last week the leaders of the three main parties, together with other senior political figures, made hasty visits to Scotland in a last-gasp bid to shore up the No vote and save the Union.

During his own visit, Prime Minister David Cameron made an emotional appeal to the Scottish people not “to rip our family apart”. Then, on what is being dubbed “Black Wednesday” for the separatists, came the news last week that the Royal Bank of Scotland and other major banks - together with insurance giant Standard Life - had announced that they would move their respective headquarters to London in the event of a Yes vote.

BP (British Petroleum) and Shell also came out against independence, discounting claims about the size of North Sea oil reserves as being “pure fantasy”, and 100 business leaders across Scotland concluded that the economic risks of separation, including higher prices across the board, were not worth taking.

These latest developments could turn out to be a turning point. The alarm in the No campaign may have subsided in the face of a poll last week showing 53 per cent No and 47 per cent Yes but both sides continue to step up their efforts to convince the electorate - indeed yesterday Cameron was in the north-eastern Scottish city of Aberdeen. Whatever happens during the next couple of days, the gap remains wafer thin, the polls divergent and the result too close to call.

Stepping back from the frenetic exchanges, it is interesting that observers attributed the turnaround in the support for the Yes vote to the second televised debate on August 25 between Alex Salmond, Scotland’s First Minister and leader of the Scottish National Party (SNP) who also heads the Yes campaign, and Alistair Darling, chairman of the Better Together campaign who was Chancellor of the Exchequer at Westminster under former Labour Prime Minister Gordon Brown.

Salmond was judged to have won this debate. I, for one, thought the honours were shared. Both performed well, though Salmond was unnecessarily aggressive and made dubious claims about issues like the future of the National Health Service and, crucially, about what currency an independent Scotland would use.

There is growing evidence that the Yes campaign has turned nasty, with bullying and threatening behaviour including intimidation of opponents - for example of high profile sporting figures like famous football players and managers as well as Harry Potter author JK Rowling and Sir Paul McCartney of Beatles fame.

While fierce discussion of the main issues - currency and other economic concerns such as jobs, pensions and healthcare, diminishing revenue from North Sea oil, European Union (EU) and NATO membership, removal of the Trident nuclear submarine base, possible border controls, loss of the use of intelligence and security services - continues relentlessly, commentators are placing less emphasis on the fundamental reasoning which drives the Yes campaign.

It is instructive to look behind the rhetoric. Despite having already achieved substantial devolution through a Scottish parliament - and with the promise of a transfer of significant further powers including fiscal autonomy and control of taxes and welfare payments - Salmond remains hellbent on full independence on the basis that ‘the future of Scotland should be in Scotland’s hands’; and this in the face of enormous risks and uncertainties amounting to a leap in the dark and possible negative effects on many aspects of Scottish life.

Many believe that the impetus for this is the visceral contempt for the Conservative Party felt by large numbers of Scots, which stems originally from the conviction of the relatively socialistic, left-leaning electorate that former Tory Prime Minister Margaret Thatcher destroyed Scotland’s industrial base during the 1980s.

Supporters of the Labour Party, which has 41 seats in Scotland, and of the SNP want higher taxes and higher public expenditure. They dislike David Cameron, who is regarded as an elitist old Etonian out of touch with ordinary people. They blame him and the Tories at Westminster for treating Scotland like a region rather than a separate country within the UK and for imposing a severe austerity programme of welfare reforms and tax cuts for the wealthiest.

Thus, the prospect of a Conservative victory at the 2015 General Election is (for them) alarming. This is influencing thousands of Labour supporters to back independence - even the possibility of a Tory success is a big trump card for the Yes campaign to the extent that fear of a Conservative future is outweighing the fear of the negative aspects of independence. Put simply, the Tories, who have retained only one parliamentary seat in Scotland, have an image problem north of the border.

Voters feel disillusioned and detached from London where, despite the advances of devolution, important decisions are taken about their lives in which they have only a limited say. They see the independence campaign as a struggle of the people against suffocating big government which ignores their concerns in far off Scotland. They want statehood, social justice, self-respect and significance as a nation in the eyes of the world.

Such patriotic demands persist notwithstanding the dire macro-economic warning; but the main issue should surely be how Scotland will fare economically and be able to pay for the socialist agenda put forward by Salmond and his SNP colleagues.

In making the case for keeping the nation within the Union, Darling has emphasised the fundamental question about what currency an independent Scotland would use. He was judged to have won the first televised debate largely because Salmond would not say what his Plan B was if the pound sterling could not be used.

The three main parties at Westminster have rejected the idea of a currency union allowing Scotland to retain the pound. Use of the euro is not a viable option, since it would take five years before Scotland could become a member of the EU. The possible alternative of “sterlingisation” - continuing with the pound without the backing of the Bank of England as the lender of last resort - is judged by the technical experts to be unworkable; and there is also the issue of Scotland taking responsibility for its share of the UK national debt.

Most recently, the Governor of the Bank of England has said that a currency union between Scotland and the rest of the UK post-independence “is incompatible with sovereignty”.

Already the uncertainty has led to a drop in the value of sterling, though it has bounced back after the latest poll. Industrial leaders and bankers are also warning of the danger of Scotland going into a deep recession following a Yes vote and of the likely threat to the economy of the rest of the UK.

The Better Together campaign has stressed that its priority is what is best for Scotland and that there is no need to separate and thus lose all the strenghts and advantages of the Union, the choice being essentially between greater devolution (including the promised large-scale transfer of more powers from London to Holyrood, the seat of the Scottish parliament) and irreversible separation. Westminster has also said that a No vote will result quickly in further devolution with the aim of securing a maximum level of local decision-making while maintaining the Union.

Though remaining neutral and ‘above politics’, The Queen herself is reported to have expressed concern about the possible break-up of the Union and a Yes vote would be a humiliation for Cameron as the Prime Minister who presided over the schism.

It could even lead to his resignation, though the drive for separation was inevitable after the Blair government gave the Scots devolution some 15 years ago - ironically, independence would actually boost the chances of the Conservatives at next year’s General Election since Labour’s 41 Scottish seats would be lost.

A parting of the ways would be a severe shock to the United Kingdon of Great Britain and Northern Ireland. Indeed, Britain - a collective term for England, Scotland and Wales - would be seriously diminished if Scotland left the Union.

Most people would agree that a country of 5.2 million, with a significant identity and a proud history of achievement, should have as much say as possible over the conduct of its own affairs. So it is worth repeating that Scotland has already achieved considerable autonomy, with further new powers to follow a No vote.

Thus, as the day of reckoning fast approaches, voters must ask themselves why there is so much pressure to go for full independence and thereby dismantle an historic and successful Union. The fortunes of England and Scotland have been interwoven in this family of nations that has brought enormous benefits to both countries for more than 300 years.

In the midst of the ongoing public debate, all concerned must surely now be only too well aware of the likely negative repercussions of a Yes vote. The most ardent nationalists will doubtless not be moved - but, for the rest, the head rather than the heart may ultimately dictate their choice.

If the Yes vote wins, there will be no going back.

• Peter Young is a retired British diplomat living in Nassau. From 1996 to 2000 he was the British High Commissioner to the Bahamas.