Boris Johnson’s double-border Brexit plan for Northern Ireland is far worse than the backstop. This is why

Johnson's alternative will scythe through both of Northern Ireland's economic arteries. The prime minister's approach is dead on arrival

A mop-haired, glittering embodiment of utter mediocrity and inexhaustible privilege stood behind a podium and declared he would never return with a polished turd and present it to the electorate.

After much scrambling, he triumphantly returned to the podium, beseeched by awestruck, adoring eyes, and unveiled his “alternative to the polished turd”.

But all there was to see was a turd – polish handsomely removed – and instead of bathing in turned milk and soured broken eggs, it is now cocooned in some kind of rotting fruit, with accompanying bluebottles buzzing around it.

This, ladies and gentlemen, is Boris Johnston's alternative to the backstop; the backstop being the thing which he voted for because he hoped doing so would make him prime minister and simultaneously the thing he opposed vociferously because he hoped doing so would make him prime minister. It has now been made worse and presented to the public with the brazen consolation that “it's no longer the backstop”.

Boris's alternative is a double-border Brexit, which will scythe through both of Northern Ireland's economic arteries – east-west and north-south. By introducing a customs border between Northern Ireland and the rest of Ireland, it adds insurmountable and unmanageable friction between all-Ireland trade and tosses a spanner into the cogs of our all-island economy.

By keeping Northern Ireland in the EU single market on goods, it creates friction in Northern Ireland to Great British trade. It also means that Northern Ireland would have to be excluded from these so-called extraordinary future trade deals that London strikes, as Northern Ireland will be wedded to the EU's single markets on goods.

To be clear, Boris's approach is dead on arrival. It is a ridiculously unworkable offer, which is why the prominent Northern Irish political leader Naomi Long described it as "farcical" and just an example of "Boris Johnson playing games".

The reason however it is worth flogging this so spectacularly deceased horse is because as a new general election rushes towards us, both this government and the DUP will claim that this was a serious attempt at striking a deal.

That will be the premise with which they will attack the EU; but it is a premise built on sand and ought to be fully scrutinised. This autopsy should also allow us to consider how Boris's double-border Brexit breaches all of the red lines the Brexiteers and the DUP strangled May's deal with, revealing their utter cynicism in how they have approached Brexit over the last three years.

The backstop was bad, but how it was added to May's Withdrawal Agreement was not. In May's deal, there was only the possibility of a backstop. Essentially, it was a sprinkler system in a house, a seat belt in a car or a helmet for a bike ride. It was there with the express hope that it would never need to be used, if everyone took care and acted sensibly.

But the DUP tore down May's deal due to the mere possibility of the backstop. They claimed this was because it would mean that Great Britain would leave the EU on different terms than Northern Ireland – but this is exactly what Boris Johnston's "alternative" also means, which they have wholeheartedly embraced.

So how is Boris's alternative worse than the backstop? Let me count the ways.

Firstly, Boris's double-border Brexit is not a fall back, but the default. From the end of the transition period, a double-border will be implemented in Northern Ireland. We are no longer looking at the possibility of a backstop being introduced if the EU-UK trade deal isn't soft enough – we are looking at the certainty of a suffocating double border on NI for at least four years after the transition period ends.

The only way that would not happen is if the DUP use their votes in Stormont (the Northern Irish local assembly which has not been sitting for almost 1,000 days). If the DUP did block the introduction of Boris's alternative, it would immediately plunge Northern Ireland into a no deal scenario again, where the safety net will have fallen away and we will be pushed off the cliff regardless. What would that cause? A double-border Brexit for Northern Ireland.

Secondly, the economic impact on NI. It is rare to see unanimity in Northern Ireland, and this can be considered the first ever example of Boris Johnson bringing people together. Across the political spectrum, whether it is unionists (UUP), loyalists (TUV), moderate nationalism and republicanism (SDLP and Sinn Fein) or moderates (Alliance and Green Party), every single one is totally opposed to Boris's double borders.

The DUP are utterly stranded – and add to that the complete unanimity of the business community. Manufacturing NI have said "the proposals are worse than no deal for Northern Ireland businesses" and will leave farms and the agri-food industry "decimated". Retail NI said it would introduce "costly and intrusive" checks that will leave Northern Irish goods "less competitive". The chair of the CBI Northern Ireland also described these proposals as the worst of both worlds for Northern Irish business.

Thirdly, the democratic dimension. Boris's alternative is not more democratic just because it envisages the DUP being able to use the arcane mechanisms of Stormont (which have made the functioning of local government impossible) to remove any certainly from the NI economy. Every four years, Stormont can vote against the continuation of the double-border system. As mentioned above, if it does so, it plunges NI into a No Deal scenario.

What happens in the very possible scenario that the Assembly has broken down is unclear. In reality, neither businesses nor the majority of people back home trust the current local political system to deal with something of such gravity; something that will hit home when the RHI inquiry findings are revealed in the coming months. This uncertainty would be such an impediment that businesses would be unable to make 5 year plans; contracts couldn't go beyond the reconsideration date. It would be an utter mess.

The DUP have consistently been irresponsible throughout this process. If they had not torn up May's deal, the UK would be entering its transition period to strike a very soft Brexit, the temperature would have decreased in UK politics and Northern Ireland would be certain that it would either be covered by a Norway-style Brexit at the end of three years of transition, or be collected up by the backstop safety net.

Instead, after pooh-poohing various offers of rescue, the DUP have obstinately clung Northern Ireland to this sinking ship, and are now trying to bundle us on to a hole-infested dingy with a seriously questionable captain.

Boris's double-border Brexit is bad; the DUP's politicking has been worse.