But the SNP has some hard questions to answer too. What future for the 6,000 jobs that depend directly on Scottish nuclear bases, and the thousands of others that rely upon them? The SNP claims they would be replaced by converting the bases to conventional defence. Workers at the base are unconvinced. Then there would be heavy decommissioning costs to factor in, and the shape of a new Scottish defence force whose naval arm (another huge expense for the independent country currently predicting a total defence budget of £2.5bn) would be based a long way from many of its principal industrial assets.