LONDON - An opinion poll showing Scottish independence campaigners have a slim lead nine days before a crucial referendum has highlighted reasons for the wider world and investors to pay heed to the Sept. 18 vote, which could see Britain lose 5.3 million Scots.
Foreign governments and financial markets had long assumed Scots would view independence from the United Kingdom as too risky a leap but the sudden swing, confirmed by another survey showing the two camps neck-and-neck, has exploded such complacency.
Losing Scotland would likely weaken Britain as a power, dent its self-confidence and make it more introverted, increasing doubts about its future in Europe.
A lot of energy has been expended arguing whether an independent Scotland could join the European Union. The European Commission said on Monday it stood by its position that Scotland would have to leave the EU and re-apply for membership.
Even more telling could be Scotland's absence from the debate about whether the rest of the country should remain part of the bloc, on which Prime Minister David Cameron has promised to give voters the final say if he is re-elected next year.
Overall, Scots are far more pro-EU than the English and if they secede in 2016 they would not get a say in the proposed 2017 referendum on Britain's place in Europe.
Without Scotland, the chances of England, Wales and Northern Ireland voting to leave the EU are greater. Scots may only account for around 4 million of the UK's 45 million voters but with opinion finely divided, that could tip the balance.
US President Barack Obama said in June the UK would be stronger and more robust if it stuck together and Washington has made abundantly clear it wants Britain to stay in the EU.
Scottish nationalist (SNP) leader Alex Salmond says the biggest threat to Scotland staying in the EU is Cameron's pledge to hold an in-out EU referendum.
Scottish independence would also alter the calculus for national politics in the rest of the country.
The opposition centre-left Labour party has 41 members of the Westminster parliament in Scottish seats while the centre-right Conservatives have only one. Take those out of the equation and the path for Labour to win power looks daunting. "In Britain, it will mean the end of any chance of Labour winning power," former Labour Europe minister Denis Macshane wrote on The Globalist website this week.
Whichever way the Sept. 18 referendum goes, Scots will still vote in a British general election next year, raising another uncertainty. If Labour won, its government might lose its parliamentary majority and fall within a year once its Scottish lawmakers go.
That loops back to EU membership since the Conservatives are committed to holding a plebiscite while Labour is not.
The irony is that the Conservatives have traditionally been the strongest defenders of the union and many would be aghast at independence even though it gave their party a permanent electoral advantage in what is left of the United Kingdom.