The outcome of next week’s referendum on Scottish independence is suddenly, and worryingly, unpredictable. Until a few days ago most observers took the view that, for all the sound and fury of the campaign, there was no chance of Scotland breaking from the rest of the UK. Now, nine days before the vote, complacency has been dispelled. On Sunday a YouGov opinion poll was the first to put the Yes campaign ahead. Yesterday sterling slumped to a 10-month low and shares in Scottish-based banks and insurers fell sharply. In places far beyond Edinburgh and London, people are starting to take a long, hard look at what Scottish independence would mean.

Following the YouGov poll, there is a discernible smell of panic in Westminster. Conservative party managers have begun asking Tory MPs if they would still have confidence in David Cameron if the Yes campaign wins. No less remarkably, the pro-union parties are now pledging to join forces this week to commit to handing more powers to Scotland in the event that the No vote prevails.

The Financial Times has argued the case for Scotland staying in the union. Sadly, in both Edinburgh and London the pro-union campaign has been poorly managed from the start.