Various leading economies have recovered reasonably well from the great crisis of 2008.

Even the US, where it all started, is reviving. Britain isn't. Fixing the UK's ailing economy was the main challenge facing David Cameron and George Osborne in 2010.

Despite a promising start, they have failed dismally. There are many reasons for this, but the main one is that Britain is not exporting anything like enough. In the league table of exporting nations, Britain languishes in 12th place.

Superficially that might not seem too bad, until you recall that Britain's prosperity was built on exporting. Now that inheritance is being frittered away. There is an insidious little fact that spells doom. We import far, far more than we export. The UK is world class at importing. These days we import, in value terms, well over £100 billion more than we export each year.

To be fair to Mr Cameron, he understands that if this continues, Armageddon indeed lies ahead. He has personally led a trade mission to India, exactly the kind of market we should be exporting more to (though we still send India aid).The Prime Minister knows that it is countries such as Russia, India and Brazil that we should be exporting to, instead of the likes of Belgium. Yet we actually export more to Belgium than we do to Russia, India and Brazil – all of them crucial, growing world markets – combined.

Mr Cameron, in his somewhat frosty, if not downright disastrous, pre-G8 summit chat in London with Russia's leader Vladimir Putin, should have been trying to open the way for more British exports to Russia. Instead he patronised Mr Putin, lecturing him about Syria, and taking the high moral ground when he had no particular justification for doing so.

Syria has nothing to do with the British economy or the future of the British people. This was inept politics, and inimical to Britain's best interests.

There is one part of the UK that is particularly well suited to grow its exports. This of course is Scotland, and I think we have here one of the more persuasive arguments for Scottish independence. I know we are currently part of two single markets, the UK itself, and also the bigger one of the EU (which is in some respects more theoretical than real).

Scotland is used to exporting to the rest of the UK, rather than further afield. Indeed on some calculations Scotland exports twice as much to the rest of the UK than it does to all other countries.

Yet it is quite possible that an independent Scotland's greatest trading opportunities would be beyond the rest of the UK, and indeed beyond the EU. Instead of being locked into a bigger economy whose very survival is threatened by its calamitous, continuing trade deficit, Scotland could become a very successful exporting nation.

And I'm not thinking only of our oil, although this should last for at least a couple of generations, and quite possibly longer. Our oil must be seen as a resource that will inevitably decrease in time, but there will be a long period to build up our exporting strength in other areas.

We are already very good at exporting high end produce, such as our whisky. Scotland's whisky exports amount to a spectacular success story that is too rarely celebrated. The whisky is not just going to Europe, where so many British exports end up, but to countries like Brazil and India. (The only problem with whisky is that the distilling process is not labour intensive.)

And as well as whisky we have world class food and, in particular, seafood. There is almost unlimited export potential here.

At the same time we are building expertise in areas like electronics and life sciences. Our universities are growing in confidence and reputation as they develop these areas.

Meanwhile I do not wish the rest of the UK any ill, but it is beginning to look as if the malaise caused by an inability to export sufficiently, combined with frenetic importing, is incurable.