Scotland stands at a historic crossroads not of its own making. The UK vote for Brexit has had its origins in the long-term problems of the Conservative party south of the Border. It was then stimulated by the rise of English nationalism, xenophobia and fears over immigration.The resulting debates had a nastiness unparalleled in recent British political history.

Because of the decision made mainly on the back of English voting majorities to leave the EU, Scotland faces an even more challenging "democratic deficit" than that of the Thatcher years of the 1980s that eventually led to the widespread demand for a Scottish Parliament.

Our future international relations with Europe have been dictated by the will and priorities of another nation. Even those Scots who detected political and cultural affinities with the people of the north of England and the Midlands in the 2014 independence referendum discussions will now have to re-appraise their preconceptions. The bogeymen this time were not only the affluent denizens of the home counties. Most of England north of the Severn and Trent line also voted decisively for Brexit. Only London stood out as a beacon of hope for Remain.This referendum has does more to bring into the open as never before the salient political differences in place north and south of the Border.

Rarely has the Scottish nation been so united on such an important issue as this referendum. Considerable majorities in all Scottish regions voted to remain in the EU. The result across the country was decisively and unambiguously in favour of Remain. All the Scottish-based political parties and their leaders argued passionately and as one for the Remain campaign.

The Scottish nation has therefore spoken loudly and clearly about its vision for the future of the country, a vision that will remain a pipe-dream under the present political structures of the Anglo-Scottish Union. Recent attempts to make that arrangement more fit for purpose through enhanced devolution can now be judged irrelevant in the post-Brexit context.

There are only two stark choices available to the Scottish people: the status quo within the UK coupled with retreat from Europe or full Scottish sovereignty alongside close association with the EU.

I for one am ever more convinced that the second of these is the best hope for our country.

Over the next weeks and months the Scottish Government will be bombarded with a multitude of ideas on how best to proceed in this dramatically changed political environment. Here are some of mine:

* A second independence referendum should take place at some point during the two-year period of negotiation between the UK and the EU on the settlement for ending UK membership.

* The Scottish Government should try immediately to build a dynamic and enduring consensus across civil society, business and all political parties for independence.

* The economic case for Scottish sovereignty should urgently be made more robust and rigorous with the help of external international experts and with an emphasis on the opportunities a renewal of EU membership will provide.

* Only when the pro-independence option has achieved a clear and enduring majority in reputable polls should the date for a second referendum be decided.

A change in the Scottish political mood seems already underway if anecdotal evidence is to be believed. For instance, of my academic colleagues who voted No in 2014, some have already moved to Yes. As one of them, the distinguished imperial historian Professor John Mackenzie, put it to me: "With Brexit, Scottish independence now makes more sense." I doubt whether he will be alone in that reasoning.

Sir Tom Devine is Professor Emeritus at the University of Edinburgh. His latest book, Independence or Union: Scotland's Past and Scotland's Present, is available from Allan Lane The Penguin Press.