THE Edinburgh Agreement signed yesterday by Prime Minister David Cameron and First Minister Alex Salmond set in motion a referendum that could result in Scotland becoming an independent country, justifying claims that the deal was both historic and momentous.

In addition to those inevitable adjectives, however, the word carefully chosen by both Mr Cameron and Mr Salmond to set the tone of the day was respect. The document signed in St Andrew's House yesterday amounted to a peace agreement over the terms of the referendum. It is not only political activists but also the majority of Scots who will feel a sense of relief at reaching this milestone on the long and tortuous road to a decision on our constitutional future. The Section 30 order transferring power from Westminster to Holyrood to enable a legal and binding referendum is complete. The referendum will be held in the autumn of 2014; there will be a single question on the ballot paper requiring a Yes or No answer to independence and 16 and 17-year-olds will be able to vote. The precise details will be determined by the Scottish Parliament following the publication of a White Paper next year. But already the landscape between now and the autumn of 2014 looks increasingly interesting.

There will be challenges but they can be overcome. For example, the wording of the question proposed by the SNP: "Do you agree that Scotland should become an independent country?" has been criticised as biased because it makes no mention of the UK. That will now be tested by the Electoral Commission. If change is thought necessary, that should not be allowed to become a bone of contention. Surely it is highly unlikely that two years from now there will be anyone who does not understand what is being asked.

Both sides were able to state (more convincingly so on the part of Mr Cameron) that their preference was for a decisive, single question. This has the advantage of testing whether a clear majority of Scots wants independence. However, since the SNP gained an outright majority at Holyrood with a mandate to hold a referendum, there has been a growing lobby in favour of increased powers for the Scottish Parliament with full fiscal autonomy short of independence. Opinion polls consistently indicate that this option is favoured by around one-third of the electorate, a similar proportion to those who favour independence and those who want to retain the current devolution settlement. It was this aspiration for enhanced devolution or "devo max" that prompted the campaign for a second question offering that option. This expressed a confidence in the competence of the Scottish Parliament to tailor policies to needs and expectations and gave evidence of a new enthusiasm among individuals and groups with no party-affiliation, especially charities and voluntary organisations, to engage in the political process beyond their immediate interests. This group, which will now be forced to choose between independence or the status quo, may feel they have been short-changed but they are likely to determine the outcome of the referendum. They must weigh Mr Cameron's statement that a vote to stay in the Union could lead to further devolution against Mr Salmond's increasing emphasis on social as well as economic benefits from independence. They will be among the most demanding in seeking definitive answers to the many questions which will arise if Scotland were to become independent; or, indeed, what will be on offer should there be a No vote.

There was unity across the political spectrum and beyond yesterday that, now that the tedious business of establishing the process is over, we can engage with matters of substance. It will be up to the politicians to demonstrate the respect avowed by Mr Cameron and Mr Salmond yesterday by engaging in honest argument, backed by sound evidence rather than simplistic exchanges of soundbites and slogans. There is a hunger for genuine information. It must be provided because no-one can decide the future of the country on the basis of blind faith or assertion. The onus is therefore on the SNP to clarify what the position of an independent Scotland would be.

The underlying principles of foreign and defence policy must be determined. Alex Salmond has still to convince his party that, contrary to long-standing policy, an independent Scotland should be a Nato member. There is no guarantee, however, that as a successor state membership would continue automatically. Membership is made even more problematic by the contradiction of trying to join a nuclear alliance while removing all nuclear weapons from Scotland. Would Scotland, if separate from the rest of the UK have to re-apply for membership of the EU, as the president of the European Commission, Jose Manual Barroso has suggested?

Could an independent Scotland truly claim economic self-determination if it retained sterling as currency and the Bank of England as lender of last resort? If interest rates were determined by the Bank in accordance with the needs of the economy in the rest of the UK, could Scotland end up with less control? This is a vital question as the shadow of the eurozone looms over any prospect of pursuing separate tax and borrowing policies while ultimately being dependent on the central bank of another country.

With comprehensive answers to all these questions and more required before the referendum, two years may be required for information-gathering and debate but in politics that is an aeon. Mr Salmond won the battle over the timing of the referendum but, however attractive the prospect of a society based on Scottish values of fairness, the economy will be the deciding factor. Mr Salmond is gambling that two years will be long enough to produce enough green shoots to convince waiverers of Scotland's potential for growth. The UK economy will also look healthier, making the prospect of further devolution more appealing.

The skirmishing over process is ended. Let honest engagement in the real issues now commence.