It’s a pity that FKB sounds like one of Vladimir Putin’s secret services, because the Federal Kingdom of Britain is what the British now need. Otherwise, the United Kingdom will become an Untied Kingdom. To achieve this federal solution, we must create across the whole of Britain what Scotland has just magnificently rehearsed for us: a democratic, constitutional moment. It is insulting to the peoples of England, Wales and Northern Ireland to suggest, as David Cameron has done, that this can be achieved in a few months.

The honouring of specific promises made by British political leaders to the Scots, including that tight timetable, must therefore be separated from a constitutional convention for the whole country. This convention should bring its proposals to an all-British referendum before the end of the next parliament. What is more, this constitutional settlement must address the question of what is done at the European level, as well as at the British (federal), national (England, Scotland, Wales, Northern Ireland) and lower levels of government. In short, what we need is a coherent, carefully crafted, popularly deliberated and democratically decided proposal for a federal Britain in a confederal Europe.

The absence of references to Europe in the barrage of first reactions to the Scottish referendum result was gobsmacking. Ukip leader Nigel Farage told the BBC that the issue now is how we create “a fair, federal United Kingdom”, which he explained as “a fully devolved, federal UK”. So federalism, the dreaded F-word, trademark of all those nefarious Napoleonic designs of beastly Belgians, is now suddenly a good thing. But why did Farage not mention the EU? After all, arrangements for a federal Britain mean deciding who has the power to do what, where and over whom. And here is a man who has endlessly been telling us, to great effect among English voters, that too many such powers have been arrogated to federalist Brussels. “Give us our country back” has been the war cry. So how on earth can we talk about a federal settlement for Britain without discussing the powers that belong to Europe?

It’s not just Farage. The British government has conducted an exhaustive review of the “balance of competences” between Britain and the EU. David Cameron proposes to “renegotiate” the UK’s relationship with the EU, and then put our membership to a Scottish-style “in or out” referendum in 2017. In what rational universe can that be separated from determining the balance of competences inside the UK? Ah, but “we don’t go in for European-style rationalism”, writes another English Eurosceptic, Daniel Hannan. “We patch things up as we go along. And we’re none the worse for it.” Really? None the worse for living in a country whose constitutional arrangements are now an incomprehensible, incoherent, right-royal bloody mess?

We have been waiting a long time for this constitutional moment. Back in 1988, a civic initiative called Charter 88 demanded a process of open, popular deliberation to reach a new constitutional settlement. This was to mark the 300th anniversary of the 1688 Glorious Revolution, which overthrew King James II of England (and James VII of Scotland – same player, different shirt). Encouraging noises were made by leading politicians such as Gordon Brown, but it went nowhere. More recently, the scandal about MPs’ expenses, exposed by the press, provoked another wave of rhetoric about a “new politics” and systemic change. I will never forget returning from three months in the US in the autumn of 2009 to find that this wave, too, had just drained away, like floodwater in old meadows. We were back in what the Scottish writer Tom Nairn memorably called Ukania, an anachronistic, discombobulated, sometimes surreal kingdom, not unlike Kakania, the Austrian writer Robert Musil’s label for the decaying Austro-Hungarian dual monarchy.

To be fair to the Liberal Democrats, they did their best in the current coalition government. They put electoral reform to a popular vote, and a largely uninterested British electorate said no. They attempted, as British politicians have been doing for 100 years (yes, you read that right), to reform the House of Lords – and failed again. In federal systems, however, the upper house is typically the place where the distinct territorial components – states, provinces – are represented, as in the German Bundesrat. That is especially necessary in multinational federations, such as the FKB would be. So transforming the House of Lords would have to be part of any serious constitutional settlement.

In crafting our new federal kingdom, we will have a lot of international experience to draw on. One of the many peculiarities of Britain is that, while repeatedly spurning federalism, it has both left behind numerous federations across the English-speaking world (Canada, Australia, India) and currently exists inside a European Union which contains many federal countries and itself has federal elements. Britain is like a man who has left a trail of puddles behind him, and lives at sea, but keeps insisting that he doesn’t like water.

People often say that because 84% of Britain’s population belongs to one of its four nations, England, it is unusually difficult to federalise. Plainly that is an issue. An English parliament would be nearly as large as the British one, and an English “first minister” – say, Boris Johnson – could play Boris Yeltsin to David Cameron’s Mikhail Gorbachev. Moreover, England does not have well-defined regions or provinces. It has historic counties, cities, towns and villages. It has the overwhelming greater-Greater London, which in socio-cultural terms extends to a radius of about three hours’ time-distance by fast train from central London. It has Cornwall, which has its own small separatist movement. And so on.

But the international spectrum of federalisms is very wide, and many of them involve what is called “asymmetric” federalism. The political scientist Alfred Stepan has identified what he calls “holding-together federalism”, as in Canada, contrasting it with “coming-together federalism”, as in the US. Some 15 years ago, Stepan presciently wrote that “should the United Kingdom ever become a federation” it would be of this “holding-together” kind.

Some of my continental European friends will have stumbled over the second part of my formula: federal Britain in a confederal Europe. “What do you mean confederal?” they will cry. “In many areas of law and policy, the EU is already beyond that.” Indeed it is, which is what English Eurosceptics are so upset about. All I wish to indicate by using this C-word is that the EU of 28 member states is a looser structure than those normally described as federal, and one in which national governments still largely call the shots. Germany is not Texas, and there is no United States of Europe. Some smaller group of member states, perhaps those in the eurozone, may move towards more federal structures, but the larger EU, of which a federal Britain would remain a part, will for the foreseeable future be something looser.

Incidentally, I Googled to check whether “FKB” is already taken. It is: by the Flying Karamazov Brothers, a theatrical troupe of comic jugglers, sometimes attired in kilts. Seems like a pretty good description of Britain’s party leaders right now.