View: Nick Clegg (left), deputy to former UK PM David Cameron, said ‘the Brexit genie was out of the box, with end of the union now more likely than not’. Photo: Suzanne Plunkett/Reuters

With the appointment of Boris Johnson as UK prime minister, at the head of a cabinet dominated by extreme Brexiteers, our worst fears have been realised. If we didn't know before, we now know that we are on the rocky road to a really rough Brexit. To paraphrase that macabre ditty from MASH, "Brexit will not be painless, it will bring on many changes".

But leaving aside economics, we need fresh thinking on the possible long-term political consequences of Brexit, no matter how remote they may seem at this time. Imagine, for a moment, that we are on a gigantic rollercoaster accelerating through space towards a not-so-distant Brexit.

Unlike the usual fairground attraction, we don't know what is on the far side. In October, when we cross into this Brexit 'event horizon', could we possibly re-emerge in a new parallel dimension?

In such a new, post-Brexit dimension we might see bizarre headlines flashing past. "England demands its own parliament", "Irish reject re-unification", "Scotland reverts to Caledonia", and even "Catalan Ambassador presents her credentials in Madrid". The impact of Brexit will extend far beyond that geographical entity, formerly known as 'These Islands'.

Consider a scenario where the first political consequence of a bad Brexit will be a boost to the cause of Scottish independence. Recent studies confirm that the Scottish oilfields will not run out in the near future, as claimed by unionists. An independent Scotland would have a viable economy. Recently, former UK prime minister Gordon Brown said that Boris Johnson as PM would be the "best recruiting sergeant ever for an independent Scotland".

Possible membership of the EU could further tip the scales in favour of Scottish independence in a second referendum. Former UK deputy prime minister Nick Clegg noted that: "The Brexit genie was out of the box, with the end of the union now more likely than not."

Should Scotland secede from the UK, pressure will increase on Northern Ireland to move towards unification with the Republic to recover its membership of the EU. There is, however, an alternative to Irish re-unification - an independent Northern Ireland.

The main theme of Seamus Mallon's new book is that Irish unification should wait until a majority of Northern unionists are in favour. This proposal, which he calls "parallel consent", could well gain increased support. After all, do the southern Irish really wish reunification against the will of the unionist's community?

Besides, the Republic would be plunged into a depression if it had to confront the double whammy of a no-deal Brexit and, at the same time, replace the UK subvention to the North in a united Ireland. Whatever, latent enthusiasm for re-unification would rapidly dissipate.

Moreover, in Northern Ireland's 2011 census, the latest available, 21pc of Northern Irish identified themselves as, just that, Northern Irish, as against British, or Irish. Think Rory McIlroy, rather than Arlene Foster or Michelle O'Neill. As pointed out by communications specialist Brett Templeton, Northern Ireland could be a viable state with an economy comparable to Portugal or Czech Republic, especially if the UK agreed to debt write-offs.

In this scenario, at some point, the North chooses independence, rather than re-unification, in order to rejoin the EU.

Such a development does not rule out ultimately moving towards a united Ireland.

The next step would be a possible coming together of three Celtic nation states, Scotland, the Republic and Northern Ireland. This would be gradual, at first probably limited to cultural co-operation. However, if it moved towards a political union, Northern Ireland could have the economic support of Scotland, Ireland, and the EU.

The Isle of Man, a crown dependency deprived the right to vote in the 2016 EU referendum, could also be invited to join such a confederation of Celtic states, which I shall call Celtonia. Celtonia should not be confused with the Kingdom of Celtonia, an absolute monarchy ruled over by King Donald-James and featured on MicroWiki.

Assuming Wales remains with the UK, Celtonia would comprise over 12 million people. Its combined territorial area, land and seas, would make it one of the largest states in the EU. In time, with the melting of the polar icecap due to climate change, Celtonia could become a maritime power. Its logical capital could be Belfast, and its flag, who knows? Possibly a Tricolour, or Union Jack, of blue, green and orange?

Finally, in another generation, a Liberal-Democrat government in England and Wales decides to hold an EU re-entry referendum.

In the meantime, faced with economic and political consequences outside its control, our Government keeps its options open. It rightly plans for the worst-case scenario and hopes for the best. Above all, it should nurture its friends and avoid making enemies.

However, post-Brexit, for starters, Ireland should show more understanding for Scotland's aspirations for independence.

We don't know who our new BFF will be when we come through the Brexit 'event horizon'.

Irish Independent