Economics:Opinion polls north and south of Hadrian's Wall show a majority favouring Scottish independence, with a leading banker endorsing the idea, writes Marc Coleman.
However similar at birth, different fortunes can make twins turn out very differently. Looking at each other now across the Irish Sea, the economic difference between Ireland and Scotland couldn't be more evident.
The two countries have all the characteristics of twin nations; similar population size, similar cultures and the same challenges in terms of having to build economies on the edge of Europe beside a big neighbour. That, unfortunately, is where the similarities end.
By 2044, Scotland's population will fall by a quarter of a million while, in the last decade, the population of the island of Ireland overtook that of Scotland. By 2019, there will be more people in the Republic than in Scotland. One of the reasons for this is that Scots now have the lowest life expectancy in the OECD.
In what is becoming a vicious circle, these social outcomes are now bringing Scotland's economy down with them. Between 1980 and 2005, GDP growth in Ireland averaged 5.2 per cent, in Norway, it was 3.1 per cent, but Scotland's GDP growth was just 1.8 per cent on average over the same period. Government revenue is declining, while land and property prices are stagnating.
Like Ireland in the 1950s and other regions of Britain today, Scotland's brightest and best are fleeing towards the already highly congested southeast of England. The results are a low business start-up rate and a weak service sector.
According to the IMD competitiveness yearbook, Scotland now ranks 30th globally in competitiveness terms, well behind Ireland, Denmark, Norway and Finland.
Scotland ought to be one of the world's richest countries: Scots invented the television, the telephone and a host of other things - economics for example - without which the modern world would be unrecognisably different.
Massive oil reserves, had they been in the hands of an independent Scotland, would have given Scotland the kind of initial booster that the the Common Agricultural Policy and EU structural funds did for Ireland. But for centuries its genius has fled west to the US or south to London. It's a familiar story. Like Ireland, Scotland's domestic economy was too weak to provide those opportunities.
This year, for the first time, opinion polls north and south of Hadrian's Wall show a majority favouring Scottish independence.
They also show the Scottish National Party, led by economist Alex Salmond MP, enjoying a consistent lead over other parties in Scotland. Next May - 300 years after joining the union - Scots may decide to begin managing their own economy.
Until recently, the idea of Scottish independence would have been seen as a far-fetched response to Scotland's problems. No longer. Last month former Royal Bank of Scotland chief and leading British banker George Matthewson endorsed the concept. The support is also gaining ground in England, with recent opinion polls showing a narrow majority of English voters supporting the idea.
Little wonder. English taxpayers subsidise Scotland to the tune of about £3,000 (€4,417) a year for each Scottish person. Scottish migration to London is also a significant contribution to the chronic over-concentration of Britain's economic activity in the southeast of England.
Whatever the constitutional and/or political issues at stake, independence - at least in an economic sense - seems to make a lot of sense. For a peripheral economy with a falling population, the power to lower its tax burden compared to England could be a vital strategic tool in reviving economic activity. No longer what they were, the tax revenues from oil reserves off Scotland's coast would - if transferred to a Scottish government - still compensate for a significant part of the subsidy the Scots now receive.
A Scottish parliament would also have the power to frame tax policy. Lower taxes do not guarantee economic success, but are a prerequisite. The chancellor - himself a Scot - recently lowered the UK's rate of corporation tax from 30 to 28 per cent. But with a host of competitors, including Ireland and the EU accession states, having rates of between 12 and 20 per cent, Scotland's rate needs to be much lower.
Despite being traditionally to the left of Labour, the Scottish National Party has strongly embraced the doctrine of cutting corporation and income taxes.
More intriguing still is the possibility of monetary independence. Since 1707, when Scottish parliamentarians were bribed into voting for the union, Scotland has retained the right to print its own bank notes (a right, interestingly, that Mr Brown tried to remove last year but failed). Euro membership would pose a dilemma for Scotland. The overwhelming majority of its trade is with England. On the other hand, Scotland is failing to attract foreign direct investment with anything like the success of Ireland.
Joining a single currency area of almost 400 million consumers - together with Scotland's low cost base - could provide attractive for multinationals looking to serve markets on both mainland Europe and Britain.
Achieving fiscal and monetary autonomy would not necessarily deprive Scotland of one of the benefits it currently enjoys from its relationship with England: a whopping fiscal subsidy. EU membership safeguards its access to trade in goods and services and ensures free movement of people.
With Ian Paisley and Gerry Adams forming a devolved government in Northern Ireland, the previously unthinkable notion of Scottish independence is becoming increasingly thinkable.
