The SNP has fired the starting pistol on its drive for independence but now faces a contest that will be more like a steeplechase than a flat race.

The Nationalists are brimming with confidence, following their stupendous result in the Holyrood elections and have been boosted by a £1m addition to their independence war chest from Scotland’s former makar, the late Edwin Morgan. By contrast, all the opposition parties appear to be flat-footed at best and at worst in total disarray.

At the SNP’s triumphant conference in Inverness at the week-end, the “I-word”, which the party hierarchy was once rather coy about, was on everyone’s lips. Alex Salmond committed his party to campaigning “full square” for outright independence in his conference speech.

Yet he clearly realises that independence is no foregone conclusion and, like the racing man he is, he is hedging his bets. That is why on Saturday he reminded delegates that the SNP had two fundamental aims: not just independence but also “the furtherance of all Scottish interests”.

Hence the referendum will have not only a straight yes/no question about independence but the fall-back of “devolution max” (full fiscal autonomy but defence and foreign affairs remaining with Westminster).

Though some of his party’s die-hards believe there is less chance of achieving their ultimate goal if there is a compromise option on the ballot paper, Mr Salmond is a pragmatist and, rather than coming away empty-handed, would accept what amounts to second prize.

For now. As the party’s referendum campaign chief Angus Robertson acknowledged yesterday, to win the SNP will have to convince many Scots who voted for unionist parties in May.

Meanwhile, though we are hearing what amounts to a reprise of the SNP’s old catchphrase of “Scotland’s oil”, the First Minister recognises that the coming constitutional debate about rights and responsibilities does not all flow in his favour.

Yesterday he acknowledged that Scotland would “accept our obligations” on its share of the UK national debt (currently around £77bn). There are big questions to answer about the armed forces, social security, pensions, sterling and the BBC in an independent Scotland. Most difficult of all, perhaps, is the issue of when and on what terms Scotland could join the EU.

The Coalition Government is only just waking up to the SNP challenge. It would be unwise and probably self-defeating to attempt to seize the initiative on either the wording or timing of the referendum. Instead, Labour and the Coalition partners should be holding the SNP to account much more effectively.

The party has moved on from the culture of girn and grievance that once characterised the nationalist movement but it is still unclear what independence would mean either constitutionally or economically. That is why most Scots remain to be convinced that their country would be better off out of Great Britain.