What is George Osborne’s grand plan for Scotland?

Alex Salmond with David CameronMichael Moore, the Scottish secretary, will address MPs at 4.30pm today to explain why the Westminster government is offering Alex Salmond the chance to hold a legally-binding referendum on Scottish independence.

Ostensibly, the answer is that government legal advice says that any “consultative” referendum could be open to challenge in the courts. But there is another, political reason. If Westminster offers the power to have a referendum, it can also tie in certain conditions.

The two things unionists want to stop are:

  1. Salmond delaying the referendum until 2014 or later, by which time the first minister might have built up a sense of unstoppable momentum and;
  2. A third option appearing on the ballot, dubbed “devolution max”, which might appeal to those nervous about full independence.

Over the weekend, reporters were told that both concerns would be addressed in today’s proposals: the legally-binding referendum would have to include only two options (“yes” or “no” to independence), and a time limit of 18 months.

It took ministers only 24 hours to realise they had scored a serious own goal. By including the 18-month window, they gave the SNP an obvious reason to reject the deal and accuse Westminster politicians of interfering in Scottish politics.

By Monday evening, the 18-month time window had been scrapped: instead the exact timescale would be decided in conjunction with Scottish parties.

But the incident showed just how discombobulated Westminster parties have been by the rise of Salmond and the increasing support for independence. The coalition is so concerned in fact, it has put George Osborne, generally reckoned to be the Tories’ finest strategist, in charge of the cabinet committee looking at the issue of independence.

Osborne has already stumbled with his first move, having been forced to drop a part of his referendum offer at the last minute. The question now is what he will do when Alex Salmond inevitably rejects this offer: will he enforce a referendum on the Scottish people and risk looking like he is interfering from London, or will he be forced to let Salmond once again set the pace of the debate?