The Catalans and Basques will be watching carefully; and further afield, separatists in Flanders, northern Italy and elsewhere will be jumping up and down with joy if Scotland votes for independence

Everything is connected to everything else, as Lenin was fond of remarking. If Scotland votes for independence on September 18, a horrendous possibility which now looks more likely by the day, it would trigger a series of highly unpredictable events with immense knock-on effects on economies, financial markets and countries around the world. It would be an event of a magnitude that too few in industry and in finance have fully grasped.

Europe and Britain would soon find out that independence can be highly contagious. Once one country decides to smash itself up, others will follow; the momentum will change dramatically. The English in particular remain remarkably relaxed about the fate of the UK – but the rest of the world is watching in amazement as one of the most successful and prosperous countries in the world looks increasingly set to be broken up.

The end of the UK would be a massive global story; it would act as an extraordinary catalyst for secessionist movements. When was the last time that a Western country broke up, let alone in a peaceful, democratic manner? Czechoslovakia doesn’t count as its divorce was a byproduct of the end of the Soviet Empire. Ditto Yugoslavia, which suffered a dreadful war. Astonishingly, one of the most recent break-ups was of the UK itself, first time around, when Ireland left in 1922.

The consequences will, therefore, be explosive for the economy, financial markets, business, political elites and all of us; the pound’s slide has only just started. It will fall again if the polls continue to shift in favour of a “Yes” vote; and it will fall further if the nationalists triumph. It will then continue to slide when the full scale of the political and constitutional chaos in Westminster is laid bare, and as the long and nasty negotiations between London and Edinburgh continue.

David Fuller's view

Hopefully, this is an overstated risk.  Nevertheless, a yes vote in Scotland’s referendum, unthinkable only a month ago, is a potential black swan for stock markets.