The debate on independence versus the union has already seen battlelines drawn, with the political camps anticipating the sound and fury to come. But Scottish independence and self-government are not about an old-fashioned nationalist movement drawing from reactionary ideas, but a profoundly modern, pro-European, centre-left politics. A powerful, plausible, non-partisan case can be made for why independence would be a power for good for Scotland and the rest of the UK. First, Scotland is a relatively rich nation which, when we factor in the 91% North Sea oil monies, could be one of the most prosperous countries in the world. Independence would allow Scotland to have proper debates about how to nurture business and entrepreneurs with a different set of ethics from the spiv capitalism of the City of London, and to take considered, long-term decisions about investment and public priorities.

Despite its wealth, Scotland also hosts the worst concentrations of poverty in western Europe and the most shocking and devastating health inequalities of anywhere. Independence could bring a sense of mission and purpose to tackling what is Scotland's real shame, the poverty, exclusion and dislocation for hundreds of thousands in a nation that prides itself on its egalitarian character. Public services north of the border increasingly see themselves as inhabiting a different universe from down south. Scottish services embody principles of equity, collaboration and simple lines of accountability, and Scotland wants to preserve this distinctive approach and resist the encroachment of public sector "reform" agenda seen in the English NHS and schools.

Then there is the Scotland of the public sphere. How a nation represents itself and is represented is a crucial part of any democracy. At the moment we have an unsatisfactory situation whereby large parts of the media such as the BBC are disconnected from contemporary Scotland, not broadcasting, commissioning or portraying the many cultures and voices of the nation. This would change dramatically if independence occurred, aiding a new ecology of the public sphere.

Independence would also give Scotland a greater voice internationally, with the prospect of a warm welcome from friends and neighbours in the EU who are fed up with UK hectoring. All of this not only changes Scotland, but England too. One argument used to keep Scotland in the union is the pessimism of modern English progressives who plead not to be left with perpetual Tory governments.

This is a false reading of history. In postwar elections the Tories have only won a majority of the English vote once in 1955, the same year they won a majority in Scotland. English democratisation would be aided by Scottish self-government, allowing radicals on both sides of the border to oppose the current way British politics does business. Here lies the prospect of wider cultural transformation and change. Over recent decades a debilitating avoidance of responsibility has grown, of blaming others whether it be Labour or Tories, or Westminster in general. Breaking that vicious cycle of gripe and grievance is only possible by embracing greater responsibility at every level of society.

What have we to be scared of? Independence promises a nation less "Scotland the Brave" and more "Scotland the confident". It allows England the chance to find its democratic voice. And it enables those of us who fear the rightward lurch of politics and the debasement of public discourse to make alliances against the institutional capture of the British state by corporate interests.

Most of all, Scottish independence is about maturing and growing up, about people recognising that they have the power to shape their collective future. It is a powerful, positive story, and the only people who should feel threatened are the narrow elites who gain so much from the status quo. A post-British politics would allow for a very different kind of Britain and Britishness to arise. That's why large elements of Scottish society and opinion are galvanised and enthused by this historic possibility.

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