Amid the clanging of history being forged in British politics, the Irish border question remains.

Boris Johnson has followed through on his threat to try and eliminate the backstop and in the process is tearing up the commitments the British government made to protecting the all-island economy and North-South cooperation in the Joint Report of December 2017.

That report was a solemn, if hard fought, agreement between the United Kingdom and European Union that allowed the divorce negotiations to move into the second phase, looking at the future relationship and agreeing a transition so that businesses would not face a cliff-edge on 30 March 2019.

On Wednesday a team of six British officials, led by Johnson's chief negotiator David Frost, proposed gutting the backstop. Out would go all the measures ensuring frictionless trade, no regulatory or customs checks, protecting the all-island economy and North-South cooperation .

"They listed the paragraphs [of the Withdrawal Agreement] they disagreed with," says one source briefed on the talks.

"Once you strip the backstop out you end up with just the free movement of people, EU citizens rights and the single electricity market. The rest is hollowed out."

Furthermore, London proposed that whatever replaced the backstop would be the end point.

The backstop, as is, is constructed as a bridge to a free trade agreement that would, it had been hoped, remove the need for the backstop since that trade relationship would be so close that no checks or controls would be needed on the Irish border.

Boris Johnson, however, does not want such a close relationship, at least not one so close it would solve the border conundrum.

Officials were dismayed by this opening gambit but not surprised. "It’s not completely surprising," says one source, "because it’s consistent with the new approach".

That approach was articulated during and even before the Tory leadership race. Johnson always saw the Irish border as a phony problem that was used by Remainers to keep Britain in the EU. But diplomats wanted to wait and see.

The official EU position was that Theresa May’s deal was closed, but privately capitals felt Johnson should get a fair hearing.

"It will be a very hard call," one diplomat said in May. "The tone and the goal that the new leader sets for himself are important. Margins are incredibly slim and will always have to take into account the Irish position first and foremost."

However the tone and goal Johnson set on his arrival in Downing Street on 24 July were both strident and triumphalist. Filling Number 10 with Vote Leave foot-soldiers, not least its campaign director Dominic Cummings, heralded a confrontational approach to Tory rebels, the House of Commons and the EU.

Soon it seemed he was engaged in not one but two games of chicken.

"He’s trying to turn the tables on the rebels by insisting that the only way forward is No Deal or his deal," said one EU official in late August. "It’s a way of turning the tables on the EU by saying, work with me otherwise it’s No Deal. That is incredibly dangerous, because you’re trying to get a deal through just on the sheer force of velocity."

It was also an inversion of Theresa May’s final faltering attempt to win over Parliament. For her it was "my deal or no Brexit". For Johnson, it had become "my deal or No deal".

Johnson tried to temper his do-or-die bravado with occasional remarks that No Deal was a million to one chance. Following his meetings with Angela Merkel and Emmanuel Macron, Johnson insisted the EU wanted a deal and was ready to turn.

Once again, a British prime minister was mistaking nuanced politesse for a change in policy.

The G7 summit in Biarritz seemed the high-point of a heady honeymoon period. Johnson cleaved close to the EU line on Iran and promising the UK would be an enduring partner on world affairs. However, his belief the ice was cracking on the backstop was misplaced.

"Biarritz didn’t mean the EU has any illusions about Johnson," says one EU official. "Fast forward a couple of years and a trade deal with the US and there’s no guarantee that the UK will stay as close to the EU as he suggests."

His repeated claims of "real momentum" were increasingly at odds with reality. Johnson had described Angela Merkel’s supposed offer of 30 days to do a deal on the backstop as a "blistering" timescale, yet 16 days of the 30 have elapsed and London has yet to table a formal text (save for David Frost’s exchanges with European Commission officials on Wednesday and Friday).

On Tuesday, Brexit coordinators from 27 member states were briefed by Stephanie Riso, a senior EU Task Force official. She told diplomats that there was nothing on the table from London.

"There are no concrete proposals," said one official briefed on the meeting. "Nothing has been put on the table, not even really a proper sketch or hint of a plan. We’re waiting. But for the moment there is zilch."

It was also becoming clearer Johnson was reneging on the Joint Report commitments to protecting the all-island economy and North-South cooperation. "It’s moving from frictionless border to as little friction as possible," said the official, "which is not the same thing. That would have a huge impact on the Northern Ireland economy."

Indeed, drowned out by this week’s Westminster drama was sharper evidence of the potential impact of a No Deal Brexit on Northern Ireland.

On Wednesday, Karen Wheeler, the former head of the UK’s Border Delivery Group told the Commons Brexit committee that London’s plan not to impose any checks or tariffs on goods coming in from the South would cause problems "within days, even hours" for Northern producers. Such a scenario would only be sustainable for "a number of months".

In another chamber, Andrew McCormick, the top civil servant in the Executive Office warned of the social impact this would have.

"If there’s No Deal there is a hard economic border immediately," he told MPs.

"All trade [in the South] has to comply [with EU single market rules] or be illegal. If there are no checks there’s no legal basis to trade. So our producers would be unable to export to the south unless they pay the tariff, and the tariff would make them unviable."

Senior figures in the Northern Ireland Civil Service have been issuing increasingly stark warnings to Whitehall about the impact of No Deal on Northern Ireland, with mixed results.

"Officials have got it and understood it," says one source, "and some are saying it to ministers privately. There’s still a bit of denial at ministerial level. It just doesn’t suit their narrative that No Deal is manageable."

Amid such intensifying anxiety Dublin, Belfast and Brussels are all wondering what Boris Johnson’s ultimate plan for the Irish border is.

His chief negotiator was vague about what would replace the backstop if, as London is demanding, it is stripped out of the Withdrawal Agreement, but the assumption is that Johnson will push for some concoction of what are known as "alternative arrangements".

Before exploring what exactly these are it is worth recalling how a Northern Ireland-specific backstop turned into a UK-wide one, and one which Johnson insists is a trap to keep the UK in the EU.

When the Joint Report was converted into the draft Irish Protocol it envisaged Northern Ireland retaining large sections of single market rules for goods and other areas, and remaining within the EU’s customs union.

This was the logical outworking of what London and Brussels had signed up to in the Joint Report. If the free trade agreement was not ready or close enough, or if "alternative arrangements" such as technology and other solutions were not ready or didn’t work, then as a last resort the backstop would be invoked, ensuring seamless trade, protecting the all-island economy – and the single market – and avoiding any disruption to North-South cooperation.

"The DUP said no straight away," recalls a senior UK figure involved in the negotiations at the time. "We’re not having Northern Ireland treated any differently from the rest of the UK. The danger of a customs border on the Irish Sea was not just a DUP problem. Theresa May and others were saying the union was so important that they couldn’t even consider that."

This caused considerable bad blood in Dublin and held up progress between March 2018 and the final days of the negotiations.

The breakthrough was the brainchild of Olly Robbins, Theresa May’s chief negotiator. Make the backstop UK-wide, but do it on a temporary basis.

"Olly Robbins had the idea that if you made this UK-wide it had the benefit of giving you the temporary customs solution for the whole of the UK," recalls the source, "so all the supply chains across the UK would gain the benefit of continuing to be in a customs union temporarily beyond the implementation period, so you get more time to adjust to whatever it is you move on to."

It was a UK idea which caused unease in Brussels, but from May and Robbins’ point of view it neatly dealt with the twin problems of the DUP and the British manufacturing, who relied on seamless trade to sustain a just-in-time supply chain model.

"All the way through this period," says the source, "you’ve got Confederation of British Industry (CBI), the car industry, constantly lobbying government on customs, through the Chancellor [Philip Hammond], the Business Secretary Greg Clark, some of it coming into the PM directly. Everyone knew clearly that the manufacturing industries, in public and in private, wanted us to remain members of the Customs Union of some sort."

Although the EU was initially reluctant, London pushed it throughout the summer and autumn, until it was enshrined within the Withdrawal Agreement as a detailed, legally complex customs union between the UK and the EU, with special provisions for Northern Ireland.

The appeal for Theresa May was that, while the ultimate goal was a "deep and comprehensive" free trade deal as quickly as possible, if that took longer than expected and if the flexible transition period ran out, the backstop would kick in and companies would not face a cliff edge.

"It was a temporary bonus," recalls the UK source, "coming from the clear understanding that the [transition] period, 18 months or so, wasn’t going to be long enough to sort out your free trade agreement".

While the EU was processing this idea, it was quickly disparaged by large sections of the Conservative Party.

The idea had been submerged into the Chequers plan for a close future relationship between the EU and UK, and from that point support foundered. It was Boris Johnson, indeed, and David Davis who led the resistance.

"They were saying, surely this turns into a trap," says the source, "there will be no incentive for the EU to move away from this arrangement."

Theresa May’s team tried to convince them otherwise.

"What they were told at the time was: the EU don’t like the backstop any more than you do. It’s bending EU law out of shape in a way that they would prefer not to. They are effectively allowing the UK to be a member of the customs union without being in the customs union: tariff free, quota-free, rules-of-origin free."

Johnson and Davis were not impressed, and resigned after Chequers.

Former British prime minister Theresa May addressing her Cabinet at Chequers

Ultimately it was the advice of the Attorney General Geoffrey Cox QC, that it could be difficult for Britain to exit the UK-wide customs union that spelled its downfall in the House of Commons.

In a desperate attempt to win Parliament’s support, Theresa May put Cox himself on the negotiating team which went on in early March to secure a legally-binding addition to the Withdrawal Agreement by way of a Joint Instrument.

This enhanced the ability for the UK to seek international arbitration if it felt the EU was acting in bad faith in order to trap the UK in the customs arrangement. Ironically, despite intense last minute talks in Strasbourg on 11 March involving Theresa May and Jean-Claude Juncker, Cox did not substantively change his legal advice and the Withdrawal Agreement fell a third time.

However, in Strasbourg the EU also agreed to give a more full-blooded commitment to replacing the backstop with "alternative arrangements".

A Joint Interpretive Statement saw both sides make a "firm commitment to work at speed on a subsequent agreement that establishes by 31 December 2020 alternative arrangements such that the backstop… will not need to be applied."

A specific negotiating track would be established to consider both "existing and emerging facilitative arrangements and technologies".

On 7 March, four days before the Strasbourg deal, the Brexit Secretary Steve Barclay had already announced three advisory groups which would explore how quickly technology and other facilitations could be realised with a view to replacing the backstop in short order.

One group was comprised of trade and customs experts, a second brought in business and trade union figures, and a third cross-party parliamentary group was established.

All three would feed into ongoing work across Whitehall and ultimately into London’s negotiating position.

One month later, an organisation calling itself "The Alternative Arrangements Commission" (AAC) was created by a Tory-donor and hedge fund millionaire Sir Paul Marshall with a view to promoting technological and administrative solutions to the Irish border "within two to three years".

Confusingly, it included a "parliamentary commission" and was co-chaired by Tory MPs Nicky Morgan and Greg Hands. Steve Barclay, who had just created three groups comprising a total of 33 experts and an engagement group of MPs, then launched the non-governmental group’s interim report himself on 29 June.

Brexit Secretary Stephen Barclay pictured in a meeting with EU's chief Brexit negotiator Michel Barnier in Brussels in August

Boris Johnson called the AAC’s findings "brilliant". Dublin was wary of making any official pronouncements on what is seen as a freelance operation, despite the heavy imprimatur of Steve Barclay and Boris Johnson.

Officials from EU member states were briefed by the European Commission on the contents of the report. The Commission said that any alternative arrangements to the backstop would have to meet five tests.

They would have to ensure the avoidance of a hard border, comply with the EU’s customs rules, ensure that Ireland was treated no differently to any other member state, comply with WTO rules, and protect the all-island economy.

So what are these alternative arrangements?

The British government’s first major paper on the Irish border in August 2017 recommended a customs waiver for SMEs, the use of the Common Transit Convention, a trusted traders scheme, and "equivalence", where the EU and UK would recognise each other’s animal health and food safety, or SPS, standards as similar.

The Alternative Arrangements Commission itself fleshed out further ideas such as mobile SPS checks away from the border, WTO exemptions under the Article 21 GATT security clause, special economic zones and a common rulebook for agri-food between Ireland and the UK, which would compromise Ireland’s place in the single market.

Dublin and the EU have a fundamental problem with alternative arrangements.

That is, that whereas the backstop reconciles Brexit and the Irish border in a holistic way, with a blanket solution that would mean both sides of the Irish border following the same rules, alternative arrangements, on the other hand, takes as the starting point the reality that both sides of the border would be following different rules.

Alternative arrangements then effectively try to mitigate the impact through technology, exemptions and efficiencies.

While the backstop is fiendishly complex, the concept of a modern border is relatively simple.

The authorities on both sides need to know what goods are crossing the border. They need to know that they comply with the criteria which allow them to cross. And they need to know they can prevent the entry or exit of these goods if need be.

As Dr Katy Hayward points out in a recent paper on alternative arrangements, the backstop focuses on the second requirement, in that it removes the need for customs procedures and regulatory checks because both sides of the border are following the same rules.

If goods are automatically allowed to cross, then the authorities don’t need to spend too much time worrying about what the consignments are or how they might be prevented from entering.

The paper assesses each of the key alternative arrangements in turn as to how they might apply along the Irish border. Each one has, according to Hayward, a member of the government’s advisory technical group, merit in making borders more efficient, but notable drawbacks in the Irish context.

The idea of exempting SMEs and micro-businesses, which make up 94% of North-South trade, from customs and regulatory requirements is tempting, but will still pose a potential risk when it comes to food safety, fraud, and the issue of bigger companies resenting having to comply with onerous and costly controls.

As for trusted trader schemes, they "[do] not typically give traders a license to cross anywhere along a land border but rather only speeds up the process of crossing the border when they reach the designated point of entry".

Becoming an Approved Economic Operator (AEO) in order to qualify for such a scheme can be expensive and prohibitive for smaller firms.

Finally, if the backstop is replaced by alternative arrangements then the rules on both sides of the border will be different. That means the authorities will need to know what is crossing and how to prevent it crossing, if necessary.

The border then becomes harder, with more controls, more inspections, higher levels of surveillance, the use of approved and unapproved crossing points and so on.

Smartphone apps, barcode scanning, Radio Frequency Identification systems, GPS tracking, drive-thru X-ray scanners are all coming on stream in the management of borders globally, but they all require cost, personnel and infrastructure.

Ultimately, argues Dr Hayward, the costs, intrusiveness, bureaucracy and infrastructure implications will all potentially inhibit the consent of border communities.

"Any monitoring of movement across the border will be taken by some residents as politically objectionable and resonant with practices during the days in which the border was securitised frontier," she writes.

"This is highly significant if we bear in mind the need for public buy-in for technology to work at all."

How close is London to putting forward concrete proposals on alternative arrangements?

The process appears to be fraught with the complexity of getting all of Whitehall familiar enough with the issues in an Irish context in order to put forward credible ideas that the EU, which is already sceptical, will simply reject because they don’t pass the five tests.

There are also signs of unease among external experts in the technical advisory group that the group risks providing Boris Johnson with the cover that he is serious, especially since he seems in thrall to the non-government Alternative Arrangements Commission.

One member of the technical panel is alarmed that, given the evaporating time frame, there is no sense of urgency, pointing out that there have only been two plenary sessions and three workshops since it was launched in March.

"If they were serious they would have called group meetings urgently, around the clock, to consider these things in all seriousness and detail," the expert says, "but there’s been no sense of building on the expertise".

However, another panel member take a more sympathetic approach. "The civil service have been very engaged," the expert says. "They’ve had Michael Gove, Steve Barclay along, relatively senior people. When you’re in those meetings it feels like they’re taking it seriously."

One member of the panel believes that what he calls a "less structured approach" is down to the fact that Whitehall is having to move faster than the civil service normally does. He also believes it is vital that he can cast a cold eye over ideas that simply won’t work.

"Some of the things tabled raised my eyebrows but it may be necessary that they’re tabled in order to once and for all draw them to a conclusion," he says. "Perhaps they need me to slaughter the unicorns to make sure they are slaughtered."

For now the opening exchanges between David Frost and the European Commission give little hope that an agreement can be reached by the end of October, notwithstanding the parliamentary efforts to rule out a No Deal exit.

There is increasing speculation that Boris Johnson could be forced to revert to the Northern Ireland-specific backstop. That would at a stroke remove the claim that the UK is being trapped and unable to pursue an independent trade policy and the Commission has let it be known it’s a change they could make overnight.

The DUP would be furious, but there are precious few options remaining. It may be conceivable that some "alternative arrangements" could simultaneously be given a higher status, with the option that they might take over some of the role played by the backstop.

"The UK is in such a bind at the moment that they may need something," says one source close to the alternative arrangements activity, "something that gives confidence to those who are worried that the EU have trapped the UK and it can’t get out".

Boris Johnson has talked about an all-Ireland animal health and food safety regime, and hinted there such an idea could extend to industrial goods.

The problem is that there is no detail on this, and also that the more he heads in that direction, the more it starts to look like the backstop.

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