IT’S easy to become overwhelmed by all the Brexit confusion but just occasionally Brexit still throws up something so bizarre it requires closer examination.

A case in point is Ruth Davidson and David Mundell threatening to resign if Northern Ireland gets a deal to stay in the single market. At first I thought “good for them, standing up for Scotland and demanding that if Ireland gets special treatment after Brexit, Scotland should as well” – but not a bit of it.

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What they were actually saying was that they would resign if Northern Ireland were offered a deal because they don’t want to give Scotland’s government the right to demand the same.

Essentially Scotland’s two leading Conservatives are trying to stop Remain-voting Scotland getting a deal that protects it from the worst extremes of Brexit and will threaten to resign to ensure that Scotland gets as bad a deal as possible from Brexit.

Why? It’s not as though they want a no-deal Brexit or were even remotely doubtful about the EU prior to the Leave vote.

Davidson famously campaigned for a 2014 No vote predicting disaster as Scotland would be out of the EU. During the EU referendum she was a vocal Remainer and more recently stated that she wants to “Make sure that we’ve got a comprehensive free trade agreement with the EU” … and to “trade within the single market”.

Mundell waxed lyrical on the benefits of staying in the EU: “We will be stronger, safer and better off by remaining in a reformed European Union”. That our first priority must be the single market and “we are better off – because British businesses will have full access to the single market, bringing jobs, investment and lower prices”.

So why is special treatment for Northern Ireland such a big deal that resigning becomes an option? Well negotiations with the EU and the growing possibility of a no-deal scenario hinge on the Irish border issue. The Good Friday Agreement insists on no borders, largely to stop smuggling-funded terrorist activity. The EU says there is no need for a border on the island of Ireland; just have it between Northern Ireland and the UK.

The DUP and Scotland’s extreme British nationalist Tories say “over my dead body” because it would undermine the integrity of the UK. The UK Government has been unable to come up with a solution. Largely because there isn’t one.

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So what’s the big deal? A few customs checks on the ferry as it arrives in Stranraer, some extra paper work at Liverpool docks for containers from Northern Ireland. We can all manage that can’t we? Well no, because if that is the cost of leaving the European Union there is a much older union that expressly forbids it.

Article IV of the Act of Union 1707 states “That all the Subjects of the United Kingdom of Great Britain shall from and after the Union have full Freedom and Intercourse of Trade and Navigation to and from any port or place within the said United Kingdom.”

There was an amendment in 1800 which put subjects of Great Britain and Ireland on the same footing (Article Sixth).

It restates the necessity of freedom of trade but it also goes a little further stating “that in all treaties made by his Majesty, his heirs, and successors, with any foreign power, his Majesty’s subjects of Ireland shall have the same privileges, and be on the same footing as his Majesty’s subjects of Great Britain.”

Ok, so if there was any border and restriction on trade between Northern Ireland and other parts of the UK, Scotland and other parts of the UK would in effect null and void the Act of Union, thus technically dissolving the nation of The United Kingdom of Great Britain and Northern Ireland into its constituent parts.

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That would mean a new Act of Union and a new Good Friday Agreement were needed and fast – no big deal, nothing to see here, move along.

A bunch of Lords have been cobbling together a suggested new Act of Union but there is nothing in their disjointed ramblings to solve the trading problems of Brexit, borders or the democratic imbalances in the UK. So that explains the DUP/Mundell/Davidson panic stations.

The fun begins however when you recall that both Holyrood and Westminster have confirmed Scotland as a sovereign nation.

Thus, if there were to be a new Act of Union then the old Union would cease to exist and some mechanism would have to be found to allow sovereign Scotland to sign up to the new Act for it would not be a union if forced upon us.

Ironically, then, saving the Good Friday Agreement would lead to a Brexit transition period, and a new technically independent Scottish Government would then retain its recourse to European Court of Justice and ask it to rule on whether the rUK can annex Scotland against its will.

It’s rather amusing therefore to think that this also raises the prospect of a referendum to ratify a new Act of Union or remain an independent nation.

How would Unionists sell that? Do you Scotland want to join a nation that will be run by a distant, dysfunctional and disinterested government that you didn’t vote for? Have your wealth invested outside your country but be burdened with debt that your nation didn’t create, and have those that did create it call you scroungers and subsidy junkies?

And have your ability to trade, travel and work abroad severely restricted because the new Union will operate outside the EU, even though you voted remain?

Do you want Westminster to roll back devolution, so Scotland’s parliament can’t protect you from the free trade deals we want to strike with nations like the US who will want their healthcare companies to be able privatise the Scottish NHS?

Thinking about it, that wouldn’t really be different to the offer they will have to make during an independence referendum – bring it (or at least one of them) on.