Alex Salmond is finally on the back foot over the Scottish referendum However, in Scottish politics something interesting is happening (which technically isn't a first, but is certainly a rarity). Mr Salmond is finally being put on the back foot. True, the opposition that the First Minister faces from the other parties in the Scottish Parliament, and from their inexperienced leaders, is still not strong enough. But the Prime Minister's decision to make his voice heard is having a positive impact. In that vacuum, Mr Salmond had a splendid time. He won a majority in the Scottish Parliament against a moribund Labour Party, and his supporters started doing victory laps in anticipation of the end of the United Kingdom. Yet amid the Nationalist jubilation, Mr Salmond knew he had a problem. His party might be dedicated to breaking up the Union, but Scottish voters are no more convinced of the wisdom of that now than they were 20 years ago. On the other hand, they do like the vague idea of Westminster transferring more powers to supplement the existing devolution settlement. Fearful of losing a referendum on full independence, Mr Salmond had wanted to delay, and even to offer a second question, demanding more powers, as a fall-back. In January, Mr Cameron realised he had done enough standing back. He decided to force the issue. Last month, authority was passed to the Scottish Parliament to organise a referendum, but the PM insisted that it must be held on a simple in-or-out basis and be compliant with UK law and accepted procedure. The question of expanded powers would, as Mr Cameron made clear yesterday, have to wait until after a referendum, and also involve improved arrangements for the rest of the UK. Despite much huffing and puffing, Mr Salmond effectively agreed to that formula. The Nationalists gleefully predicted that Mr Cameron's involvement would be a disaster for the Unionists, because it would look as though an Englishman - a Tory toff, to boot - was trying to boss Scotland about. On the contrary, Mr Salmond's high personal ratings have dipped slightly, as Mr Cameron sets about re‑establishing the idea that there is nothing wrong with the Prime Minister of the United Kingdom taking an interest in part of that kingdom. His intervention has also emboldened other Unionists, who will take the lead in the campaign to preserve it. For example, Alistair Darling, the former chancellor, is now pursuing Mr Salmond on the question of which currency Scotland would use after independence. There is still a long haul to go until the referendum in 2014, and Mr Salmond has many advantages, including money and campaigning muscle. But thanks to Mr Cameron, the SNP leader faces a proper fight.