If the people of Scotland vote for independence from the United Kingdom on September 18, they will be buying a one-way ticket to their own misfortune, and with consequences that will go beyond their borders affecting Commonwealth countries.

Notwithstanding the arguments of the Scottish National Party, the Scottish economy cannot sustain an independent Scotland that can deliver the welfare system the country now enjoys and pay for all the apparatus required for defense, security and participation in international affairs. Scottish nationalists do the people of Scotland no favour by glibly urging them to go it alone.

If the Scottish voters opt for independence, they will quickly learn what many independent Caribbean countries understand well – being small has very few and limited advantages in a world where military or economic power reigns supreme. Of course, Scotland's economy is bigger than all of the Caribbean economies, and its wealth and human resources are much greater. In this context, it would have a better chance of survival as an independent State than many Caribbean countries. That argument is true, but even with its greater resources, Scotland will still be a small country with little bargaining power and even less coercive muscle in the international community. It will quickly learn the disadvantages and marginalization of being small and ignored.

Scotland's reality is that it has a population of 5 million people as against the present 63 million in the UK who share the cost of Scotland's pension payments, unemployment benefits and free heath care. Scotland would be far better-off by securing greater devolution from the British government and legislature of authority over the key matters that most deeply concern the Scottish people. They have virtually achieved much of this by the fear that separation has engendered in the political establishment in Britain. The leadership of the Conservative and Labour Parties in a desperate effort to avert Scotland's separation has pledged greater authority to the Scottish Parliament and administration.

The political leadership of Britain has good cause for wanting to keep Scotland in the UK. As I have argued before, it is not only Scotland that will be diminished and made vulnerable by a vote for independence, the rump United Kingdom (UK) will also be reduced in stature as an economic and military power.

In turn, a shrunken UK will have a less legitimate claim to its current occupancy of a permanent seat on the United Nations Security Council, and as an influential member of the Executive Organs of international financial institutions such as the World Bank and the International Monetary Fund. Even with the European Union and the Commonwealth of Nations, the UK's position will be undermined. For instance, in the Commonwealth, the UK, without Scotland, will become a smaller economy than India.

The financial sector in Britain has already reacted badly to the possibility of Scotland's independence - re-enforced by recent opinion polls that indicate a sharp rise in pro-independence sentiment. The value of the British pound fell sharply against the US dollar and international investors have been warned to pull their cash out of Britain to protect themselves against the impact of Scotland's independence.

Undoubtedly, leaders of the UK's main political parties have been very worried for some time about the impact of a positive vote for independence by Scotland. But, while the vote against such a possibility appeared unlikely, none of the principal political leaders sounded any alarm for fear of creating precisely what is now happening – anxiety that the UK will fragment with a cataclysmic effect on its economy. John Major, a former Conservative Prime Minister, articulated the deep concerns of British political leaders by saying: "The vote next week is about far more than the future of Scotland. It is about the future of every part of the United Kingdom".

As polls show a distinct swing toward a vote for independence, both the British Conservative and Labour Parties have pulled out all the stops to reverse the trend. The Labour Party has called into actively campaigning in Scotland its former leader and Prime Minister, Gordon Brown – himself a Scot. It has to be hoped that, in the end, the push of narrow Scottish nationalism will be tempered and trumped by the pull of benefits within a wider union.

The rest of the world should be very concerned about a UK that is smaller in economic and military terms and as an influential voice in the world. The UK still has an important role to play in contributing to peace and security in Europe and in the world's most troubled spots. It will not be able to do so unless it has the means.

For countries in the Caribbean, a shrunken UK has several consequences. One of them is as basic as contributions to the Commonwealth Secretariat and its Fund for Technical Cooperation. At present, the UK pays the single largest share of these costs. If its economy is reduced in size, contributions will have to be recalculated placing a heavier burden on all member states including those in the Caribbean for which the Commonwealth is an important instrument in pursuing their foreign policy objectives.

The 12 Commonwealth Caribbean countries also need a strong UK in the European Community and in the Organization for Economic Cooperation and Development as an advocate for Caribbean interests. Belize and Guyana in the Caribbean community also have a vested interest in the UK remaining a robust voice on the UN Security Council because of their border controversies with Guatemala and Venezuela respectively.

Beyond the international political role that a strong UK plays for the Commonwealth Caribbean, there are a host of economic linkages including tourism, investment and development assistance that a less well-off UK will certainly be forced to curtail. And, then there is the contention of reparations for slavery. If Scotland were to choose independence in the referendum, Caribbean countries would have to add Scotland to the list of possible litigants. There were many Scottish plantation and slave owners in the Caribbean and they too benefited from huge 'compensations' paid to them at slavery's formal abolition.

Hopefully, good sense will prevail in Scotland on September 18

(Sir Ronald Sanders is a Senior Fellow at the Institute of Commonwealth Studies)

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