Leading article: Alex Salmond's separatists have a head start

The campaign for Scotland to remain within the UK has some catching up to do. So far, Alex Salmond, Scotland's First Minister and the leader of the Scottish National Party, has made all the running, having seized the initiative in the first place by announcing a referendum to take place in two years' time.

Yesterday's launch of the all-party, pro-union "Better Together" campaign, fronted by Alistair Darling, is to be welcomed, then. It is good, too, that the former Labour Chancellor is committed to accentuating the positives of the unionist cause. He started well by acknowledging that although Scotland can well survive on its own, the question is, rather, whether it is in the country's interests to do so.

While the desires of the Scottish people must, of course, be respected, this newspaper would strongly argue that the answer is no. In part, the issue is an economic one, and in this regard the SNP's assumptions about the bounty from Scotland's oil and gas deserve some scrutiny. Not only are North Sea hydrocarbons a finite resource, but even in the short term they leave the country unduly reliant on a commodity whose price is subject to sharp fluctuations.

There is also a careful judgement to be made as regards the 30,000 civil servants that the UK Government currently employs in Scotland; far more than the 17,000 retained by the Scottish Executive.

But that is not all. Scotland, through the UK, has a seat in the United Nations, is a major shareholder in the International Monetary Fund, and wields more influence in the EU than other European countries of comparable size. An independent Scotland could not have bailed out the Scottish banks as the UK Government did. Its cost of borrowing would also be higher, with a knock-on effect on interest rates and mortgages.

Then there is the thorny issue of how the SNP's proposal to stick with sterling might be made to work, with the euro crisis exemplifying in such awful detail the dangers of an attempt at currency union without full political integration. And that is before the practicalities of unpicking everything from monetary policy, to immigration, to military co-operation, to reciprocal health and welfare provision, are considered. Let alone whether an independent Scotland would inherit all the UK's existing obligations, opt-outs and international treaties, or would need exemptions of its own.

Scottish nationalists cite the Arbroath Declaration of 1320 as a beacon of freedom – a reference underscored by Mr Salmond's timing the referendum to coincide with the 700th anniversary of Bannockburn. In response, Mr Darling insists that Scotland now has the best of both worlds, with a fair degree of autonomy, yet still girded by the security that comes from being part of a larger bloc: Scotland is stronger within the union just as the union is stronger with Scotland. How right he is. For all the tricky politics involved, it is a case that the Prime Minister must also help him make.

But the arguments in favour of retaining the union are not all focused on economic and political realities. The strongest of all are those of the emotions. After 300 years of shared history, the ties between the two countries run deep, for all the routine Scottish cheers in support of the England football team's opponents. Being Scottish, or indeed English, has never before been mutually exclusive with being British. It need not be so now.

Thus far, the debate has been largely restricted to either narrow nationalist tub-thumping or low-down political tactics such as the wording of the referendum. Mr Darling et al must raise the stakes if the union's cause is to stand a chance, with so formidable a political campaigner as Mr Salmond.