27/03/2013 09:32 GMT | Updated 26/05/2013 06:12 BST

The Choice Facing Scotland Is Changing, and So Must the Debate

"A NO vote would relegate Scotland to the bottom of the Westminster agenda - the idea that Holyrood would gain new powers in these circumstances is fanciful."

Nicola Sturgeon, deputy first minister of Scotland, 27th January 2013

As the debate in Scotland rumbles on the SNP and the wider YES campaign are promoting the message that the only way to get change is to vote YES, and that the union is stubborn and impossible to reform without splitting it in its entirety. It's a widespread view, and it usually only takes a few minutes of debating devolution in cyber space before someone gives you the 'jam tomorrow' line, but is it really true? Many point to the unionist promises of the 1978 referendum, and Lord Home's insistence that if enough Scots voted NO then they would be rewarded with something just as good. However, the impact of Lord Home's intervention is hard to quantify, and even the most cynical would have to accept that there are big differences between then and now; not least the existence of the Scottish parliament itself.

There is a school of thought that says constitutional reform only happens when there is a nationalist threat. While it is fair to say the rise of the SNP has sped up the devolution process, is it really fair to say that a desire for independence was central to the formation of the Scottish Parliament? It may have been a factor, and many would point to George Robertson's MPs mantra that devolution would 'kill nationalism stone dead', however, it's important to remember that the campaign for the parliament was lead by the Scottish Constitutional Convention, a broad devolution campaign preceded by the Labour-lead Campaign for a Scottish Assembly. Polling from 1997 shows that support for independence was only 26% at the time of the initial referendum, and support for the SNP remained unchanged from the 22% they achieved in 1992.

Even in its early days the parliament developed a distinctive and more progressive footprint than Westminster; with early Labour lead administrations scrapping tuition fees, abolishing section 28 and bringing in free healthcare for the elderly. These gains were built on by successive SNP governments, who abolished the graduate endowment fee, scrapped prescription charges and froze council tax. These changes have all been possible under the current legislation, but do they also represent the limits of the parliament's powers? Since its establishment devolution has been regarded as a process rather than an event, with the implicit assumption being that greater powers would be devolved over time. At points the pace of change has felt slow, which was one of the reasons for the SNPs landslide in 2011.

Since then the referendum has put the debate on fast forward and amplified the pressure for greater constitutional change. This was evident in the passing of the Scotland Act 2012, which felt like a rushed and inconsistent collection of new powers, and didn't seem to be underpinned by any particular narrative or vision of devolution. Now it looks certain that all three of the pro-union parties will go into the vote with their own detailed proposals for greater powers and an enhanced settlement. Many will question their sincerity, but if nothing else it is indicative of a public desire for greater autonomy. The Liberal Democrats have already produced a lengthy document outlining their federal vision, leading Labour MP Douglas Alexander has called for a new constitutional convention in 2015, with the party's own commission due to report prior to the referendum, and now Conservative leader Ruth Davidson has joined them in calling for greater autonomy.

The point I'm making is not that devolution is perfect, or that independence would be bad (on the contrary, it's the constitutional settlement I support) but rather that the idea of a NO vote being the end of the process is without foundation. Devolution has always had lifeblood of its own and that would continue. A similar process is happening in Wales, where the electorate has recently voted to increase the powers of their Assembly, despite there being very little threat of Welsh independence.

My view is that there are certain red lines that Westminster wouldn't give up without a fight; Scotland's role in the military, the nuclear deterrent and access to oil and resources. Outside of those keystone issues I can't see any Prime Minister dying in a ditch politically to protect Westminster's right to control air passenger duty, fuel tax or a whole range of other domestic powers. I'm not suggesting that Cameron and co would sign them away at the drop of a hat, but I find it hard to believe that they wouldn't be considered as part of an expanded devolution package.

The very existence of the Scottish Parliament means that Scotland's choice is no longer between Edinburgh rule and London rule; it's between full independence and further devolution. Unfortunately this isn't coming out in the debate, but it will as the opposition parties become clearer on their specific proposals. This needn't be a bad thing for nationalists; if nothing else it moves the direction of political gravity towards greater autonomy, and more importantly it concedes a central pillar of the nationalist argument; that the best people to decide on matters affecting any country are those that live in it. It also nullifies the inevitable attack that independence means all things to all people; of course Brian Souter's vision of independence will differ from Tommy Sheridan's, but is that any more of a divergence than the difference between Ruth Davidson's vision of devolution and George Galloway's?

However, it also means is that those of us who support independence can't just focus on why it's better than the status quo; we also have to make a case for why it's a better choice than devo-max, devo-plus or anything in between. With the vote still a year and a half away there is little point in trying to predict the result. However, one thing we can be sure of is that there will still be an SNP government the morning after. In the result of a YES vote they will begin negotiations for Scottish independence, but if there is a NO vote they will need to work with the unionist parties to strengthen the parliament. All polling suggests that a clear majority of Scots are in favour of greater autonomy, or powers short of independence, so the unionist parties would be committing electoral suicide if they renege on their promises and refuse to back it. Whatever the result there will be major constitutional change, with more on the way, the question is at what pace.