The Scottish independence referendum poses a very good question but suggests an inadequate answer. The question is: where does power lie? This is not a marginal problem to pose in a 21st century democracy. It cuts to the heart of a deep crisis in the relationship between people and politics. But the answer implied on the ballot paper is a geographical one: power lies in either London or Edinburgh. Most Scots – and most of the rest of us – know that while this choice is far from meaningless, it also rather misses the point.

Power lies only in part with elected governments, whether in London, Edinburgh or even Washington. It also lies with global corporations, with media monopolies, with unaccountable oligarchies, with mighty financial industries immune even to their own reckless follies. Hence the real question that Scots have to decide: will independence shift the balance of power away from oligarchy and towards democracy? If the answer is yes, independence is well worth having. If no, Scots should look to Ireland’s recent experiences: independence that does not give citizens some power against global forces is fragile and shallow – and, as Ireland learned in 2010, can be revoked by the financial markets.

It is striking that the referendum has turned out not to be about certain things: Braveheart, kilts, the saltire, hating Sassenachs, Rabbie Burns, Renton’s rant in Trainspotting about the Scots allowing themselves to be “colonised by wankers”. The language of tribal nationalism is starkly unspoken. For an issue of such moment, the debate has been remarkably civilised and thoughtful. If you’re Irish, you can only look on in admiration and envy: Scotland has the opportunity to acquire independence without murders, without civil wars, without partition, without a toxic bitterness being passed on through generations. There have been a few nasty incidents and there may be more but having an egg thrown at you or being abused on Twitter is not quite like being put against the wall and shot.

Even more startling, Scotland’s independence can be consensual. England and Wales, to their enormous credit, have already accepted Scottish sovereignty, and whatever happens in the referendum there is no going back on that decent and gracious decision. Scotland may or may not become an independent country but it is – already and without argument – a free country.

The debate's civilised nature, however, tells us something important: there are no absolutes at stake here. There is no violence not because the Scots and English are nicer people than, say, the Irish and British were a century ago, when their conflict descended into blood, but because everyone knows that this whole thing is about nuances, complications, qualifications. There is no apocalypse on the horizon: a yes vote will not create a Scottish year zero in which everything is reinvented from scratch. Equally, a no vote will not be a triumph of the British state, a once-and-for-all vindication of the land of hope and glory.

For while it is the Scottish Question that is on the ballot paper, it is the British Question that is really on the table. Alongside the absence of nationalist sentimentality on one side of the argument, there is something equally remarkable on the other: the inability of the no campaign to articulate a coherent, passionate and convincing case for the existing United Kingdom seems, from the outside, quite staggering.

This state has existed for 307 years and has shown remarkable resilience in adapting to radical change, from the loss of empire to the loss of Ireland. But it now seems incapable of projecting to a large part of its population a positive sense of what it stands for. Even if the no side wins, it will have done so largely through fear on the one hand and, on the other, a belated recognition that in order to save Britain, its current configuration must be destroyed. If a Britain survives this moment, it will be a polity transformed by some kind of federalism.

Why has the British establishment so little to say for itself? Because Britishness was never really an ethnic identity. It was, after the empire, a set of institutional structures for contesting and distributing power: mass political parties, trade unions, churches, railways, a national health service, universities and so on. The “deep state” and the City of London continued to hold immense power, of course, but it was reasonable to believe that there was a democratic realm that could weigh in on the side of ordinary people, and convenient to call this realm Britain. The problem now is that almost all those democratic forces are hugely diminished. The no side in Scotland has found itself trying to defend a status quo that scarcely exists any more.

The Scottish referendum is in this sense a symptom of a much broader loss of faith in the ability of existing institutions of governance to protect people against unaccountable power. This is why the campaign is not particularly nationalistic: the loss of faith at its heart is Scottish and English and Irish and Welsh and European and American. The demand for independence just happens, for historical reasons, to be the form in which Scots are expressing a need that is felt around the developed world: the urgent necessity of a new politics of democratic accountability.

And as symptoms go, this has been a rather healthy one. It is impossible to have visited Scotland in recent days and not to have been exhilarated by the sheer vigour of democratic engagement. Scotland at the moment is what a democracy is supposed to be: a buzzing hive of argument and involvement, most of it civil, respectful and deeply intelligent. This energy has been unleashed not by atavistic tribal passions but by a simple realisation: for once, the people have some power.

The pleasure of witnessing this democracy in action is tempered by a nagging question: why is it not like this all the time? It is not, as the Scots have proved, because people are apathetic. It is because they don’t have, in day-to-day politics, a sense that they can control things. What really matters now is whether after the referendum, Scots return, like the rest of us, to a state of frustrated powerlessness, or can sustain the democratic energy that has been unleashed. If that’s to happen, neither a mini-Westminster in Edinburgh nor a lightly modified Britain will be much use. If the referendum is to be the start of something big, it must also be, for international democracy, the start of something new.