Nissan has been betrayed by Brexit ideologues

There's something tragically appropriate about the fact that the most high-profile British industrial story, as the country staggers in the direction of a no-deal Brexit, should involve Nissan.

The proximate cause of the Japanese company's reversal of its decision to build a line of SUVs at its Sunderland plant was the collapse of European demand for diesel vehicles. But as its management has made perfectly clear Britain's departure from the EU was a factor too.

It's worth recalling why Nissan is here in the UK at all. In the 1980s Margaret Thatcher practically begged the Japanese firm to establish a plant in Sunderland, promising a smorgasbord of public subsidies and support to make it happen. Such interventionism jars with the popular image of her administration as a callous band of laissez-faire ideologues obsessed with the City of London and happy to let former northern industrial powerhouses crumble.

Yet the biggest lure for the Japanese was not those subsidies, but the UK's position in the European common market. As Keith Joseph, Thatcher's industry minister, wrote in a memo to Thatcher: "Nissan had chosen the United Kingdom because it gave them access to the whole European market. If we were outside the community, it is very unlikely that Nissan would have given the United Kingdom serious consideration as a base for this substantial investment."

Another irony about the Nissan investment is that France and Germany were, in those days, hostile to the idea of allowing Japanese car firms a production bridgehead within the European common market, fearing the impact of the competition on their own domestic automotive manufacturers.

Thatcher overcame those protectionist European impulses and indeed made the creation of a free market, regulation-harmonising, "single market" among the European member states a personal priority. Yet now, 33 years on, we have nominal Tory Thatcherites not only insisting that the UK must leave Thatcher's single market but also airily dismissing the Brexit concerns of Nissan's Japanese management - a management which their heroine was once so keen to court.

The suggestion by the chair of the European Research Group faction within the Tory party, Jacob Rees-Mogg, that because Nissan's former boss Carlos Ghosn stands accused of embezzlement in Tokyo that nothing the company has to say need be taken seriously, shows how far this wing of Conservatism has drifted into denial. The ERG prefers conspiracy theories and witch hunts to listening to firms' worries about trade barriers. Before the private "letter of comfort" to Nissan from the business secretary Greg Clark in 2016 was finally published on Monday, the great fear among these hardliners was that this letter had made unacceptably positive noises about Britain remaining in a customs union with the EU.

Another lip-chewing irony over Nissan is that the Labour leader Jeremy Corbyn has been fretting recently about the restrictiveness of EU aid rules and some of his supporters have gone as far as using this as an argument in favour of total rupture. But the Clark letter revealed £ 80m of promises of UK government assistance for Nissan, with £ 61m of grants formally offered. If such state aid is forbidden under "neoliberal" EU law, as some "Lexiteers" seem to suggest, the EU's institutions and courts have been surprisingly tolerant of it.

The air is thick with accusations of "betrayal" over Brexit. But the reality is that it is Nissan and other foreign corporate investors in the UK that have been betrayed; betrayed by political extremists ignorant of history and by those who find their ideology preferable to reality.

Brexit insurance that is worth having

The Irish "backstop", the legal clause that offends the sensibilities of hardline Tory Brexiteers - to the point where they would be prepared not only to immolate their own government but even possibly lose Brexit altogether to be rid of it - is often described as "insurance".

It's insurance, of course, for the people on both sides of the Irish border in that it means - if there's no trade deal between the UK and the EU by 2021 - a hard border on the island will not descend. But it's also insurance for people in the rest of the UK too, given it's not in their interests, either, to jeopardise the Good Friday Agreement. That latter benefit should really be more emphasised in the UK debate.

Yet why do we need insurance in life? The truth is that we often don't. Buying a warranty on a new microwave or vacuum cleaner is a waste of money given the cost of the insurance and the statistical likelihood of the product failing. These are immensely profitable contracts for retailers, which is why they push them so hard at the tills.

And insurance companies are so profitable, in part, because people have a tendency to over-insure against the wrong things. We like the peace of mind that comes from the possibility of relatively small claims, even if we would usually be better off foregoing them.

The better reason to buy insurance is to cover losses we wouldn't be able to cope with. "Insure only those things you cannot afford to lose," is the advice of the economist John Kay. "You need insurance against your house burning down, but not for replacing the bedroom carpet. You need insurance against being hospitalised in the US, but not for an extra night's accommodation because your plane is delayed."

Some Brexiteers don't actually care very much about the Irish border. A clean break with the EU matters more. Some, apparently, privately think the Irish are impudent for using the leverage with the EU to demand a backstop at all and should "know their place".

But let's assume those who have voiced such opinions are outliers rather than representative. Let's assume mainstream Brexiteers genuinely want to avoid a hard border in Ireland but believe that the backstop is unnecessary, that it's overkill.

They place a low probability on it being needed because they are confident we'll conclude a free trade deal by December 2021 and that this will include an unproven technological fix to the problem of Ireland being in the customs union and single market and Northern Ireland being outside both, something that would ordinarily require border checks on goods and agricultural produce passing between the two.

But consider who is calculating those probabilities. And consider their record. When he was Brexit secretary, David Davis predicted that the UK would establish a free trade deal with the EU, and a host of other countries, the "very next day" after we formally depart on 29 March 2019. We know now that's not going to happen.

Liam Fox, still the trade secretary, predicted that a post-Brexit free trade deal with the EU would be the "easiest in human history". It's certainly not looking that way now.

Yet, in fact, this isn't the right way to weight up the value of insurance. For insurance is not to cover eventualities we expect to happen with a high probability, but those that we fear. Even if one put a low probability on a trade deal not being ready in time, that does not imply a backstop would be a mistake.

A good insurance policy protects us against worst case outcomes. That's what the Bank of England was thinking about when it put together its no-deal Brexit scenario modelling. It wanted to test whether the UK banking system could cope in the face of an even an extreme economic and financial shock.

That's why, even if one is sceptical of the assumptions used in climate warming models showing rising temperatures as carbon dioxide levels in the atmosphere rise, one can still be in favour of radical decarbonisation efforts. The risk of a super-heated planet is too great to take (and the cost of shifting away from fossil fuels is eminently bearable).

"Skin in the game," is the solution favoured by Nassim Nicholas Taleb for powerful people who propose to run risks affecting others. He gives the example of monarchs who personally led their armies into battle, and sea captains who go down with their ships. "Skin in the game means consequences when you are wrong as much as when you are right," he says.

Creating a political system with such clear symmetric incentives is difficult. But it's nevertheless a useful way to think about those loudly insisting we don't need the Brexit insurance of an Irish backstop.

The worrying echoes of the First World War's beginnings in May's approach to Brexit

In 1909 the British empire was locked in a frantic race with Germany for naval military supremacy. The continent was carved into antagonistic power blocs of states and kingdoms, jealous of each others' colonies. The atmosphere was thick with anticipation of a major new European conflict.

In that year, a Labour Party MP and journalist Norman Angell came to the rescue, with a pamphlet designed to put this febrile talk of European war to bed. Angell's thesis was that the cost of a general war to the European economy was so manifestly enormous that it was highly unlikely to happen - and, if it did, would be soon over. The economic self-interest of nations - of the individual citizens and businesses in them - would block military conflict.

"What is the real guarantee of the good behaviour of one state to another?" Angell asked. "It is the elaborate interdependence which, not only in the economic sense, but in every sense, makes an unwarrantable aggression of one state upon another react upon the interests of the aggressor."

Angell's pamphlet was a bestseller. It was bulked out into a book called The Great Illusion, which was widely translated and published around the world. Its thesis was, of course, just about as misleading as any book's has ever been, either before or since.

We stand in the middle of Angell's ashes today as we mark the hundredth anniversary of the end of the First Word War. Ten million soldiers and ten million civilians died between 28 July 1914 and Armistice Day, 11 November 1918. Economic self-interest did not save them.

A chapter by David Jacks, part of a new book released last week on the economics of the Great War, shows that the shadow of the conflict was enormous. The arteries of global commerce were thoroughly ruptured in 1914. World exports did not return to the pre-1914 growth path until the 1970s.

The extreme economic dislocation that followed the end of the First World War arguably prepared the ground for the Great Depression, mass unemployment and the rise of fascism that culminated in the Second World War.

The counterfactual question of how the lives of our great-grandparents, grandparents - indeed all of us born over the past 120 years - might have been different if the nations of Europe had not slithered over the lip of the cauldron of war in 1914 is mind-meltingly large. The lesson of Angell's error is, of course, that no forecast of how nations will behave can rest solely on an analysis of economic or commercial interest. But it's a lesson that we still find it a hard to absorb.

Sometimes we hear that a no-deal Brexit, which leads to us crashing out chaotically from the European Union next March, is most unlikely because it would plainly be economically destructive for all involved.

British firms understand it. European firms grasp it. The majority of MPs don't want it. Ergo, it's really not going to happen, however much it gets talked up. But accidents do happen. And especially in complex, yet fragile, geopolitical environments.

AJP Taylor has fallen out of fashion these days. But he was the first popular TV historian. And in the 1970s he enthralled British viewers (speaking to them plainly without notes and without sophisticated production techniques) of his theory of the causes of the First World War. According to Taylor, the military powers in 1914 were tightly constrained by the practical logistics of moving soldiers and supplies around the continent by railway.

"All the mobilisation plans had been timed to the minute, months or even years before and they could not be changed. Modification in one direction would ruin them in every other direction…. Any alteration in the mobilisation plan meant not a delay for 24 hours but for at least six months before the next lot of timetables were ready."

These constraints, according to Taylor, meant that a single spark - the assassination of an Austrian Archduke in Sarajevo - exploded into a wildfire; this was "war by timetable".

Maybe, maybe not. Historians have been debating the causes of the First World War ever since it ended and have been unable to settle on a consensus.

Yet when we think about Theresa May's decision to trigger Article 50 in March 2017 - setting the twoyear countdown running on our exit from the European Union - before she had even reached agreement within the Conservative Party, let alone the country, over what sort of post-Brexit vision to pursue, it is hard not to hear disturbing echoes of the Taylor thesis of calamity by timetable.

It's hard not to be reminded of how potentially dangerous are those leaders who have painted themselves, and their countries, into a corner.

Food for thought for Brexiteers

One could tell a surprisingly comprehensive history of the Brexit project by simply talking about food.

From curved bananas to non-recyclable teabags, Eurosceptics have long relied on myths and scurrilous half-truths about groceries to stoke public resentment over the supposed red-tape lunacy of the European Union.

More recently, Brexiteers have taken up the (mostly false) idea that the EU discriminates intensely against African smallholders in order to protect its own inefficient farmers. The pro-Brexit Tory MP Daniel Kawczynski posed sombrely in front of a tray of supermarket lemons this month in order to lambast "the EU protectionist racket".

But it's not just Africans who will benefit from Brexit. The Sun informs us that after we leave the EU the Great British shopper will all be able to save 40p on a pack of butter and 31p on a punnet of strawberries and much else besides thanks to the tariff-torching free trade deals we will inevitably sign with other countries.

Brexiteers seem to believe that a way to a Briton's support is through his or her stomach. Taking control is framed as taking control, above all else, of our grocery basket.

But it's not all one way. The Brexit food fight is a symmetrical one. US "chlorinated" chicken has become the spectre at the feast, a symbol of what the powerful US agricultural lobby will ram down our throats as the price of an inevitably unequal American trade deal. And few of the no-deal consequence warnings cut through to the public quite as effectively as the threat of a sandwich shortage.

They sometimes try to conceal it, but the agenda of some Brexiteers is plainly deregulatory. One of the reasons the forecasts produced by a small band of pro-Brexit economists show long-term gains for the UK, when every other credible study shows precisely the opposite, is that their models assume we will in future shed all our domestic product standards, including on food imports, and trade on what are known as "world prices".

But the lines between ideological fantasy and reality are becoming blurred. UK ministers insist there will be no compromising of high food standards after Brexit. They also say that in the event of a no-deal Brexit they would waive customs and standards checks on trucks delivering produce from the EU in order to mitigate transport bottlenecks and supermarket shortages. They have not said what, in those circumstances, is to stop some criminal group importing unsafe produce to the UK. Perhaps they believe it's a risk worth taking.

Regulation 1168 of the European Council, from 2011, is just the sort of Brussels red tape that Brexiteers love to hate. It lays out a host of requirements for food manufacturers, from providing detail on the geographical origin of produce to its nutritional content.

But it also says that packaging should warn buyers about ingredients that can cause a dangerous allergic reaction. Fifteen-year-old Natasha Ednan-Laerouse from Fulham died in 2016 after eating a baguette from Pret A Manger which did not list traces of sesame, to which she was allergic, on its packaging.

This was not, in fact, a requirement under the EU regulation because it was a fresh handmade product, although many people, in light of this tragedy, believe this is a regulatory loophole that urgently needs to be closed. The coroner in the case said last week that he would be writing to the government to raise concerns about "inadequate" food labelling regulation.

Brexiteers will argue that this extremely sad incident has no bearing on the issue of EU membership. And in one sense they're correct. There's no reason why the UK post-Brexit shouldn't have new domestic regulations on food labelling that are even tighter in some specific areas.

Yet this, of course, is at odds with their deregulatory impulses and the dream of importing food at world prices. Moreover, it highlights a huge and still unrecognised blind spot on trade. For it is pan-European regulatory harmonisation, regardless of whether those regulations are well-designed or not, that helps UK food exporters to tap into a significant market in the EU. It is this harmonisation that dismantles what Margaret Thatcher once called the "insidious" trade barriers of "different national standards".

Assuming that the rest of the world does not join us post-Brexit in a bonfire of food standards – and there is no reason to expect that they will – our producers will have to conform to the standards of other countries if we wish to sell into their markets. Taking back control from the EU will simply mean submitting to the authority of others jurisdictions, whether that’s the US, Canada, India or wherever. And to sell into the EU we would still have to conform to the single market’s food regulations, even if we are out of it.

Yes, there are costs from regulation. It's onerous to perform tests, to fill in paperwork, print labels and all the rest. But there are vast economic benefits too.

It was 30 years ago this month that Margaret Thatcher made her speech in Bruges, seen by eurosceptics as the lighting of the torch of national resistance to Brussels. Yet earlier in 1988 the prime minister had made another speech on the urgency of completing the single market.

"There was a tendency in Europe to talk in lofty tones of European Union," she said on the subject of regulatory harmonisation. "That may be good for the soul. But the body - Europe's firms and organisations and the people who work in them - needs something more nourishing."

 Food for thought for Brexiteers today.

Beware ideologues who would inflict pain on others

At the peak of the global financial crisis a decade ago there were some who insisted that politicians and regulators should sit back and just let crumbling banks go bust.

No bailouts. No rescues. What we needed, they said, was creative destruction.

There was plenty of other similarly terrible advice in the following years. There were those who argued that governments needed to slash state spending, even at the very height of the global recession. There were those who shouted that emergency money printing by central banks would rapidly result in destructive inflation. When that crippling spike in prices failed to materialise, they switched to warning that "quantitative easing" would be a form of slow-working poison for the economy, keeping alive zombie companies. They began urging central bankers to put up interest rates as soon as possible.

Although governments, tragically, started to cut deficits far too early, before the recovery was secured, they ignored most of these suggestions. And thank goodness. Such policies would have led to massive economic destruction, and severe social suffering.

To be clear, this isn't to argue that the mainstream policy view is always entirely right. The mainstream policy view before 2008 was, after all, that the banking system was well capitalised and light-touch regulation was a good idea. Nor is it a rejection of the idea that things should have been handled differently. Unlike the Bank of England, the US Federal Reserve bought other kinds of bonds than just government debt as part of its money printing. The Swedish central bank imposed negative interest rates, where others baulked at going below zero. Iceland put bank bosses on trial. There are legitimate arguments about how the crisis was handled over which reasonable people can disagree.

This isn't about nuanced policy debate. This is about the dangers of arguments plainly based on ideology rather than evidence, that brush aside the question of trade-offs and uncertainty, whose advocates are suspiciously blasé about the risks of pain that will be borne by others, who seem to luxuriate in their aura of almost Old Testament righteousness.

But, of course, the fact that the advice of the zealots was ignored gave them an opportunity too. It allowed them to say: "Things would have been better if you had done what we said." And there's sadly a market for this view of the world. There are plenty of people today who will parrot the line that that money printing has been a disaster, that governments should have cut spending in the bust alongside the private sector, that the financial system should have been allowed to fail in 2008.

Now we can discern a similar dynamic over Brexit. A small caucus clamours for no-deal. A tiny group of economists, whose work has been comprehensively and repeatedly debunked by genuine trade experts, claim it would actually deliver a tremendous boost to GDP. The boss of Wetherspoons, Tim Martin, says crashing out, offering the most risible argument, would be a "huge gain" for consumers, even as the rest of British industry dissolves into terror at the prospect.

We may yet crash out. But the likelihood is, still, that we will not, that responsible voices and reasonable politicians will prevail.

What follows then? The likelihood is that we will be told by the ultras it was because we didn't drink the Kool-Aid that we haven't woken up in their Brexit paradise, that the quisling politicians messed it up, squandered the chance.

It's tempting to hope that the headbangers get what they want. Then they will have to own the fallout.

Then they will be forced to face up to the reality of their ideas and to be held directly accountable. Yet this is to misunderstand their psychology. For the irredeemably ideological it is always someone else's fault.

There's always a treacherous stab in the back.

However, responsible policymakers do not knowingly inflict harm on populations in order to win an argument.

There is no simple way out of this trap of responsibility. So how to neutralise the siren voices? We can't run repeated experiments on economies to discern the merit of various strategies as we might in a video game simulation. The best we have is history and natural experiments.

The US authorities failed to rescue its collapsing banks in the 1930s. The result was an all-encompassing financial panic and, ultimately, a loss of one-fifth of the economy and 25 per cent unemployment. Greece was forced by the rest of the eurozone to cut government spending in the midst of its bust. The result was strikingly similar to America in the Great Depression. Countries that didn't see demand sucked out of their economies did better. The European Central Bank raised rates and did not start QE until 2015, some six years after the US Federal Reserve. The result was a worse economic performance for Europe since 2008 than in the traumatic 1930s, while the US recovered faster.

For most sensible people that would constitute evidence. But such crutches are not available with Brexit.

There's no historical precedent for a country leaving a massive trade and regulatory bloc like the EU. And we're the only one doing so now.

The fact is that there will always be irresponsible ideologues, zealots as dangerous as they are deluded. It's a test of the maturity of our politics, our media culture, our society as a whole, in how we deal with them.

Sadly, we've not been doing too well on that front in recent years.

Brexit ideology will be bad for exports

If visions from ministers were effective in boosting UK exports we would long ago have surpassed the £1 trillion target set by George Osborne when he was chancellor.

Last year we managed total overseas sales of £616bn, according to the latest official data. With just three years to go before we were supposed to hit the magic £1 trillion figure, we need exports to grow at an average annual rate of 17 per cent. So only triple the average rate of 5 per cent achieved since the turn of the millennium.

Could it be a sign of intruding realism that the trade secretary Liam Fox has quietly dropped the £1 trillion target and replaced it not with a nominal target for exports, but a target as a share of GDP? Fox, in a speech yesterday, said he wants total UK exports to be equivalent to 35 per cent of GDP, up from the current share of around 30 per cent. That at least gives him the opportunity of hitting the mark via a big UK recession and consequent collapse in GDP even if exports sales don't actually budge.

The past eight years have been a nightmare for the Greek economy, but its exports as a share of its (collapsing) GDP have leapt from 20 per cent to 32 per cent.

But then perhaps realism hasn't yet breached the walls of the trade department because Fox is still burbling vacuously about the great trade "opportunity" presented by Brexit.

There's something supremely frustrating about hearing Fox rabbit on about the potent'exporting superpower'ial of selling more luxury goods to the Chinese when the preeminent trade challenge over the coming years for the UK is simply standing still.

Leave aside, for a moment, the question of our future trade arrangements with our dominant commercial partner, the EU. We also urgently need to "grandfather" the 50-odd existing trade deals between the EU and other countries, from Mexico, to South Korea, whose coverage the UK will fall out of after the post-Brexit transition ends at the end of 2020.

This is by no means a simple task, either politically or technically, as Peter Holmes and Michael Gasiorek of the UK Trade Policy Observatory have painstakingly explained. Some countries may seek to extract concessions from the UK as a price of rolling them over. And then there's a planet sized headache over "rules of origin", relating to finished exports made with components from third countries.

The details are too complicated to outline here but the bottom line is that successfully grandfathering these trade agreements would require the agreement not only of the UK and the third countries involved, but of the EU as well.

There was not a word on any of that in Fox's speech. Instead we got a cargo container of spurious assertions.

Fox spoke as if world trade intensity is booming. But it's not. Since the global financial crisis a decade ago trade as a share of global GDP has actually fallen from 60 per cent to 55 per cent. And then there's Donald Trump's trade war and the White House's attempts to undermine the World Trade Organisation, which Brexiteers routinely herald as the UK's safety net in the event of a no-deal Brexit.

Again, all this seems to have passed our chronically incurious trade secretary by.

So does the fact that the Office for Budget Responsibility, the government's own official forecaster, expects the UK's share of global trade to stagnate, not grow, over the coming years. We should probably just be relieved he didn't call the OBR traitors, trying to sabotage Brexit Britain.

But the fact is that only an incorrigible ideologue could survey the horizon in 2018 and see a vista of burgeoning trade opportunities.

The views of Fox on the Brexit negotiations are of little value given he's been kept well away from them by Theresa May. But, when asked about them yesterday, he offered this warning: "If the European Union decides that it wants to put...the ideological purity of the bureaucracy of Brussels ahead of the wellbeing of the people of Europe, it will send a very big signal to the rest of the world about exactly where Europe is heading." But the fetish for ideological purity belongs not to Brussels, but to the Brexiteers.

And that, alas, shows the direction they're dragging us.

One year to Brexit: How businesses in the most economically exposed region of the UK are coping

A sword of Damocles hangs over the economy of the North-east of England. That at least is the implication of the government's own economic analysis when it comes to Brexit.

Internal research leaked from Whitehall earlier this year suggested the North-east's economy could take a hit of up to 16 per cent from an ultra-hard Brexit, in which the UK crashed out of the European Union with no trade deal. That's compared to the 8 per cent injury estimated for the UK as a whole.

And that's a projection of the economic damage over the course of 15 years, relative to staying in the EU.

This highly export-reliant region could be damaged even more grievously in the short term if the UK-EU negotiations fail, and tariff barriers and customs inspections come crashing down, rupturing the arteries of our trade, in March 2019.

Yet the North-east was also one of the UK regions with the largest proportion of Leave votes in the June 2016 referendum, with 58 per cent opting to get out, versus 42 per cent for Remain. Just about every division of the wider region - from Sunderland to Stockton, from Darlington to Durham - voted out. And most did so by a wide margin. Only cosmopolitan Newcastle came down in favour of staying, and that was by a slim 1 per cent of the vote.

So the North-east has a decent claim to be the economic "ground zero" of a hard Brexit. Yet it's also one of the heartlands of Leave.

With just 12 months to go until Brexit, The Independent travelled to the region to see how firms there are coping with both the sharp weapon hanging over their heads and also the deep social and economic contradictions exposed by that fateful popular vote back in 2016.

Driven to distraction

In ancient Greek theatre a "deus ex machina" - or "god from the machine" - would emerge to bring resolution to a tragic human drama.

In the North-east of the 1980s, hollowed out by the secular decline of shipbuilding, coal mining and steel making, Nissan played something akin to that role. A deus ex machina to make machines. The Japanese carmaker was courted heavily by Margaret Thatcher; promised all sorts of tax breaks. But much of the allure for Nissan was the promise of unimpeded access to the vast European market. It's that access which is now, of course, in jeopardy, much to the alarm of the Japanese.

But for 30 years the deus did seem to work miracles. Nissan's Sunderland plant has been one of the most admired inward investment projects in British post-war history. The factory is considered the most efficient in Europe, churning out half a million vehicles every year, most of which are exported to the EU.

Nissan directly employs around 7,000 people but that's a grossly inadequate measure of the firm's economic importance to the region. An ecosystem of local suppliers has sprung up around it, supporting as many as 50,000 more jobs in the region by some accounts.

Nissan declined to talk to The Independent for this article. Yet Steve Bush, a gregarious officer currently in charge of automotive for the Unite union, who liaises with union representatives from Sunderland daily, is happy to emphasise the importance of the broader car industry for the region.

"It's on a monumental scale - and I don't use that word lightly," he says at the union's Newcastle office. "If there was any hit to the North-east automotive industry it would have a huge detrimental effect on the economy. I think everybody appreciates that. When I speak with tier-one and tier-two supplier firms, the first thing they talk about is Brexit. All companies are aware of what the stakes are."

Nissan's worst nightmare is official government policy; namely Theresa May's promise to quit the EU customs union. This threatens to play havoc with its cross-border supply chains. Components used in the manufacture of cars at Sunderland often travel across EU member-state borders multiple times. Tariffs imposed on each trip into the UK would obviously push up costs. But the bigger threat is delays due to new customs checks. The Sunderland plant operates a "just-in-time" manufacturing process, with minimal stocks of components held at the plant. That means even the most modest of hold-ups in deliveries could wreck its hyper-efficient operating model.

Nissan last year attempted to induce its overseas suppliers to shift to the UK to help mitigate the problem.

The government is helping to fund an International Advanced Manufacturing Park, situated right next to the Sunderland plant, to host them. And Nissan did agree to produce a couple of new models there in the immediate wake of the Brexit vote after receiving various mysterious assurances of support from ministers.

That should keep the plant running until 2022. But no one in the region believes the factory's long-term future is anything like secure.

Neil Warwick is a lawyer for Newcastle-based Square One Law. The EU specialist is highly sought after and has worked with many manufacturers in the region. Warwick, whose superficially dour demeanour periodically breaks into a conspiratorial grin, says the administrative burden of a hard border could ultimately prompt the Japanese firm to take a brutal decision.

He points out that one of their car engines crosses borders 18 times before it's manufactured. "Is it just easier to do everything in France and ship it back once?" he asks. "The only hard border you need to worry about is the UK."

Such a move, Warwick stresses, would be abysmal news for the region. "It would regress the plant back to effectively a screwdriver assembly plant. It's hugely bad for the supply chain."

There would probably be major negative downstream effects for local services firms too. Tony Roxburgh is the commercial director of North Shields-based Calibre Secured Networks, which installs IT wiring for schools, offices and call centres. His company would expect to be commissioned to do work at the new Sunderland manufacturing park if it takes off. But the future of that project, of course, all comes back to Nissan. "If Brexit had an impact on Nissan, the fallout from that is sure to have an affect on every business in the North-east," he says.

Heads in the sand

Earlier this month the Chambers of Commerce hosted a private roundtable meeting at the Hardwick Hall Hotel in the County Durham countryside. In attendance were 20 large local supply chain companies to talk about their Brexit preparations. Warwick of Square One Law, who chaired the session, recalls his opening question. "I said 'how many people have got a Brexit plan and how far along are you with implementing it?'" The result was disturbing. Not a single company even had a plan, never mind putting it into action.

One participant at the meeting described it as "head in the sand syndrome".

Small firms, and not only those in the North-east, are especially exposed to the economic disruption of a customs border. Some 134,000 small-and medium-size companies in the UK are estimated to have only ever exported to the EU. "The worrying thing is that we're not even sure if they know what's going to hit them," says Warwick.

Julie Underwood, head of international trade at the North East England Chamber of Commerce, tends to agree. "How are firms preparing? Not particularly well, in truth," she says. "The whole area of customs compliance doesn't tend to get a focus, even now."

Exports are the economic lifeblood of the North-east. And Europe is a big market. Official data shows that the value of its exports to the continent added up to £ 5.6bn in 2017. Divided by the region's 2.6 million population gives exports per head of £ 2,100, the highest of any region in the UK.

And it's not only cars, chemicals and machinery. Half of the North-east's services exports went to the EU in 2015, again the largest share of any UK region. These raw facts on trade are the primary reason why the government's modelling exercise paints such a uniquely bleak economic picture for the North-east due to Brexit.

But all this gloom about plummeting GDP and rising tariffs barriers: isn't this "project fear" all over again? Graham Robb, the founder of a Darlington-based public relations firm Recognition and head of the local entrepreneurs forum, thinks so. Back in the 1990s Robb stood as the Conservative candidate for Hartlepool, losing out to one Peter Mandelson. And he took his lead in the Brexit campaign from the former Tory chancellor, George Osborne.

"I advocated Remain with a great deal of passion," he says. "But I publicly recanted last year because a lot of the stuff we were told didn't come about. I felt foolish."

On the latest government analysis, showing that 16 per cent hit, Robb says: "Once bitten twice shy. The same people who produced that analysis were the people who gave us the analysis that it was going to go wrong before."

Robb, who has clients across the region, says he has spoken to lots of property developers who are interested in investing in the region, regardless of Brexit. He also discerns a divide between entrepreneurs and big companies when it comes to the opportunities of leaving the EU. "Amongst my peer group of owners I'd say there is a much less passionate Remain stance than there would be among more corporate entities," he says.

Warwick of Square One Law accepts the point, but adds that entrepreneurs can also be somewhat naive too.

"The entrepreneurs, yes, by their nature, they spot gaps, they see opportunities. But there's also a certain amount of ignorance," he says, citing the case of one "very famous entrepreneur" who was intensely pro-Brexit until he learned that one of the components in his manufacturing business came from Poland. "The knock-on effect on his business just hadn't occurred to him."

People power

Everything is enormous in Northumberland's Port of Blyth. Fifteen-metre high rolls of undersea cable, which will be laid to connect offshore wind farms to the mainline, line the perimeter of the South Harbour.

Even more massive pieces of trench-digging equipment litter the sprawling dockyard, like the carcasses of brontosaurus.

Biggest of all are the two jack-up barges for digging oil wells squatting at the sea-edge of the harbour; four crane-like legs towering-up above each of them.

What must it be like working among such intimidatingly colossal chunks of metal? "You get used to it, but when I saw the even bigger ship that the jack-up barge came in on (the 34,000-tonne Albatross), even I thought 'wow'," laughs Brendon Hayward, managing director of the subsea engineering company Osbit, which has a warehouse on the port.

With his blue Jaguar car, sharp-cut three-piece suit and brown winklepicker brogues, Hayward seems more like a football agent than an engineer. Hayward founded Osbit seven years ago to provide bespoke engineering solutions for offshore players such as Gulf Marine Services, DeepOcean and Van Oord. The GSM jack-up rig boasts a vast, bright-yellow exit ladder, specially designed and manufactured by Osbit.

But Hayward's Brexit concern relates to the people who bash the pieces of metal that he exports.

Official data shows that the North-east has the lowest proportion of EU workers in England. They account for just 1.8 per cent of population, less than half the 5.5 per cent average for the UK. Such figures suggest that the North-east would be relatively unscathed if the government clamped down on EU migration in the coming years, something UKIP-types insist was the clear "will of the people" revealed by the Brexit vote.

Yet many businesses in the North-east agree that workers from mainland Europe have an outsize importance to region's economy.

"The thing that I could entirely see hampering the North Sea supply chain is if the labour changes," says Hayward, whose business model is based on its promise to turn around projects very quickly. One of the local steel suppliers that Osbit used last year has a workforce which, he reckons, is 30 to 40 per cent made up of Eastern Europeans.

"If our suppliers lose 30 per cent of the workforce, and we ask for a 21-week turnaround, maybe they turn around and say, 'We can't do it.' The time element is really key to us. The client needed the system in 21 weeks. If we'd quoted 30 weeks I think they would probably have ordered it in Europe."

"Currently we can deliver really cost-effective new technology all made in the North-east and we can ship it all around the world. That is absolutely determined by available labour. If our suppliers lose that labour capability we have a problem."

If that happens, Hayward warns that Osbit could be forced to manufacture outside the UK.

Steve Bush, from the Unite union, issues a similar warning about the high proportion of Lithuanians who work for Lear Corporation, one of Nissan's local car-seat suppliers.

But the North-east is not all engineering and manufacturing. Ryder Architecture was founded in Newcastle in the 1950s. Its elegant headquarters is a converted 19th-century horse and carriage repository - what partner Paul Bell describes as a "horse car park" - close to the city's central train station. Bell, dressed in a grey jumper over a pink shirt, explains how his own business relies on overseas talent, including from Europe.

"Being able to bring in the best talent from around the world is an advantage to our industry. There's not an issue within our profession of UK jobs being under threat from immigration," he says. "Some of our colleagues from Europe have been here a number of years and they are genuinely concerned about their ability to stay."

Ignazio Cabras, professor of entrepreneurship at Northumbria University, doesn't have that problem personally. Though he was born in Italy, he has been a British citizen for the past 10 to 15 years. "I don't even remember how long," he laughs. But for many of Cabras' colleagues Brexit is no joke.

"A significant number of academics in all the five universities and colleges in the region are from the EU," he says. "We're worried. There are already concerns that a significant number might reconsider their residence in the UK." For a region that aspires to grow its knowledge economy and cement itself as a hightech skills production centre, such a brain drain is an ominous prospect.

Global Britain?

Nigel Mills and his dad built a mini newsagent empire in the North-east. Mills junior sold his 77 corner shops to Tesco in 2010, making the lanky former accountant a wealthy man. But now he's mainly interested in alcohol.

Mills' new venture is a Cumbrian whisky distiller called The Lakes Distillery. Exports are a big hope for the young premium drinks brand. But Brexit is already an obstacle.

"The biggest problem with trade is making sure that your brand meets the local regulations," he explains.

"That's one of the things with Europe at the moment - we all adopt the legislation and there's no issue. For me it's that compatibility that's as important, if not more important, than tariffs. So it was frustrating when the Brexiteers were saying, 'Let's get rid of all the red tape.' OK, now you can't export because your product doesn't comply!" But shouldn't Mills be rubbing his hands together at the promise of a new free trade deal with the United States, often promised by Brexiteers? Think of all those thirsty American Scotch drinkers, waiting to be introduced to the Lakes' new single malt. The problem here, Mills points out, is that there are already zero US tariffs on whisky imports. The barrier is local regulation, not levies.

And Mills isn't expecting the US to lower its "non-tariff barriers" for whisky.

"Because of Prohibition in America (in the 1920s) it is highly regulated. There's a complex three-stage process to get alcohol into America. You've got to have an importer, a distributor and then a retailer. I don't think they're going to dismantle their monitoring system," he says, with a shrug of resignation.

Disconnected

Back up in a factory in Blyth, they're building something that looks and moves a bit like a R2D2. Tharsus is a robotics firm responsible for the wireless-controlled automatons which whiz up and down rails in Ocado's new packing warehouse.

Only around two robots a day trundle off the Tharsus production line. But if Ocado, which owns the intellectual property for the system, succeeds in selling it to other grocery groups abroad, the demand could explode, keeping Tharsus very busy indeed.

Some of those Tharsus shop-floor workers almost certainly voted for Brexit. Why? It seems like an act of self-harm, given the region's reliance on EU trade. Many say it's because people in the North-east felt "left behind" and were venting their frustration.

Gross value added per head in the North-east - a very rough estimate of income - is the lowest of any region of the UK, except Wales, at £ 19,542 a year. The figure in London is £ 45,000. Poverty in some wards of the region is very high relative to the UK average. So is the share of the population with health problems.

But Brian Palmer, Tharsus' compact and wiry chief executive, feels "left behind" isn't the right phrase. "I would say disconnection," he says. "There's a sense that London's a long away and it's a different world."

Paul Bell, the architect, agrees. "One of my concerns about Brexit is that the focus on Brexit means other initiatives such as the Northern Powerhouse move down the agenda," he says, referencing the government's northern regeneration project, which many in the North-east already sense has become unfairly focused on Manchester and Liverpool.

Some fear Brexit will make any kind of catch-up for the North-east more difficult. Because of its relatively low income per capita, the region has qualified for development funds from the EU. In the 2014-20 round of funding the region was awarded £ 425m from two pots of EU cash, the European Social Fund and the European Regional Development Fund.

In recent years, money from Brussels has helped finance Newcastle University's 24-acre "Science Central" innovation hub and also the Baltic arts centre in Gateshead, converted from an old flour mill.

Before the referendum, the Newcastle Chronicle calculated that people in the North-east had received twice the amount of EU funding per head as in any other part of England since 2007.

"You have to find another way of kick-starting the development," says Bell.

But can Westminster be counted on to fill the gap after 2020? Trust feels in short supply, even close to home. Nissan had warned that it could reduce investment in the event of a Leave vote. But many of their own workers voted out, regardless. Many were baffled by that, since industrial relations in the plant, and indeed across the region, were regarded as exemplary. Some suspect that they weren't as good as they were made out to be, and that workers were itching to give two fingers to management.

But Steve Bush of Unite doesn't think this is the explanation. For him, many workers were misled by the mass media, particularly tabloid newspapers.

"I've spoken with workers and said, 'Why have you voted out?' and they say 'immigration'. But then you say, 'What about the guy who works in the plant with you, or lives in the next street, or next village?' and they say, 'I'm not talking about them, I'm talking about the guy on the front page of The Sun who's brought his family over etc'. And I say 'hang on a minute…'" Yet to John Elliot, the 75-year-old founder of dehumidifier and washing machine maker Ebac, it's perfectly obvious why people voted for Brexit. It's because the UK economy is up the spout and not working for ordinary people.

From his Newton Aycliffe factory, Elliot dismisses the "people were misled" argument as patronising.

Elliot, who left school without any qualifications, has developed some extensive, yet esoteric, views about what ails the British economy. And one of his convictions is that tariff protection for UK manufacturers is not necessary. "You've got to have a trade war. And you've got to have some casualties," he says, excitedly, sounding like a Pitmatic Steve Bannon.

That might seem to be a position that serves Elliot's own business. If foreign washing machines are kept out, Britons might have to buy his models instead. Yet Elliot freely admits that components for his own washing machines are imported from the EU. "The electric motor in there is from France, the pump is from Italy, the motor there is actually from Spain," he says, gesturing to a demonstration unit in an unpretentious upstairs meeting room.

Ebac also exports water coolers to the US and the EU. So isn't Elliot's firm directly in the line of fire if the kind of global trade war he advocates breaks out? "If we're going to change things for the better there's going to be some casualties and if that's us, tough! I would rather be that casualty if the economy was going to become better. Why? Because I live here and I'd like the UK to do well. We could make these things in Poland and make an extra dollar but I don't want to.

I'd rather make a reasonable profit here than a bigger profit in Poland."

And though Elliot is a local champion of Leave, he doesn't actually think Brexit itself is the main prize. "If someone said we'll sort it [the economy] out if we stay in the EU, I'd say 'stay in the EU'. I'd live with that."

Doomed to partnership

Like the enormous jack-up rigs in Blyth harbour, the economic threat of Brexit looms large in the Northeast.

The threats to trade, the potential jeopardy of the supply of skilled labour, the disappearing EU funds, the sheer difficulty for firms in planning ahead when the future is as clouded as the bottom of the Tyne on a murky day.

But also looming large is a question of inequality, raised by John Elliot. Why, if the North-east region is such a successful exporter, as everyone accepts, are incomes so low relative to the rest of the UK? Where are those rewards going? And there's the balancing act: the difficulty of weighing the needs of multinational firms with the palpable yearning among many local people for a greater degree of control over their lives; a control to be wrestled back from Westminster just as much as from Brussels.

Business leaders are in the middle of the tug of war. Those to whom The Independent spoke are proud Geordies, Mackems or Northumbrians, with a genuine feeling of loyalty to the North-east region. They sense the dangers to their businesses, but also the frustration of many of their employees.

The emotions run high, from Leavers who resent what they see as economic defeatism, to EU nationals anxious about their future. Somehow, businesses and the communities in which they are embedded must find their way through. They are doomed to partnership.

But with one year to go, the task of navigating the agonising trade-offs, confusions and contradictions of Brexit has not become any easier.

Hammond’s spring statement was no new dawn for the UK economy. It was an optical illusion

The bonanza, in the end, failed to materialise. There had been a fair amount of talk before the Spring Statement that Philip Hammond would be in a position to unveil a new dawn for our beleaguered public finances. City analysts had been chattering like South London parakeets about a potential £10bn permanent improvement in the public finances.

And the excitement had jumped the species barrier from the Square Mile to Westminster. The ardent Brexiteer Jacob Rees-Mogg had squawked about the imperative of ratcheting up spending on the struggling health service. Other Tory MPs had similarly chirruped in favour of a loosening of the Government’s austerity corset. The Chancellor himself had allowed himself to refer to “light at the end of the tunnel” in conversation with Robert Peston at the weekend.

Well the light of the tunnel may not quite have been the headlights of an oncoming train, but, according to the Office for Budget Responsibility, it was certainly an optical illusion.

The OBR did revise down its estimate of public borrowing in 2017-18 by around £5bn on the back of fuller than expected tax revenues so far this fiscal year. Yet Robert Chote and his team concluded that this was not likely to be a permanent improvement, mainly because they now estimate that the economy is overheated relative to their estimates in November. In other words, when things naturally cool down, the tax revenues will start undershooting. 

Similarly, the overall GDP growth forecast for the UK is a smidgen better this year. But next year – when Big Ben (may) ring out for Brexit– it is unchanged at a paltry 1.3 per cent. This, we should bear in mind, at a time when the rest of the world is growing at its strongest rate in years. And the expected UK growth rate is actually shaved down in the final years of the OBR’s forecast in 2021 and 2022. What the Spring Statement giveth, it also taketh away.

The Chancellor might have rebranded himself as Tigger, rather than Eeyore, but the OBR was channelling the lugubrious blue donkey when it concluded: “There seems little reason to change our view of [the UK’s] medium-term growth potential.

City scribblers earn their bread speculating about the short-term ups and downs of the economy and the public finances. But what really matters for our long-term living standards is the UK’s productivity growth potential, the amount of output we can collectively squeeze out of each hour worked and each worker. And the big picture is that productivity has been as flat as a pancake ever since the Great Recession a decade ago. Or at least that was true until the second half of last year, when we, surprisingly, witnessed the best two consecutive quarters of productivity growth since the financial crisis.

Yet the OBR doesn’t think the UK’s productivity growth engine has started roaring again, since the improvement in 2017 was driven by fewer hours being worked, rather than higher output. A similar surge happened in 2011 before petering out. Another broken promisein other words. Let’s hope they are wrong, but there’s not much reason to believe it, particularly given ongoing public spending cuts and Brexit continue to dampen the animal spirits of households and companies.

And what of that pachyderm in the living room? What about Brexit? The consensus of serious economists is, of course, that Brexit will harm our growth potential by throwing up trade obstacles between us and ourbiggest commercial partners and, probably, reducing useful immigration to boot. And the OBR is not demurring from that. Its view, articulated way back in 2016, that Brexit would damage the UK’s public finances, wiping out any “dividend” from not making annual contributions to the EU Budget, still stands. And that’s based on the assumption the Brexit process is nice and smooth.

In the short-term, the OBR, conceded the economy had held up better than it expected immediately after the plebiscite. But this was partly due to the unexpected global growth spurt, partly because households seem to have dipped into their savings to support their spending. Moreover, as the OBR stressed today, it simply doesn’t regard the Office for National Statistics’ estimates of how the economy performed since the vote as reliable.

In short: as you were. The new Brexit dawn for the British economy looks remarkably like the old one.

On trade, Trump and the Brexiteers are not as far apart as you might expect

When it comes to trade, liberal Brexiteers are cut from a very different cloth from Donald Trump. Or so we're led to believe.

Trump wants protection. But Brexiteers want more trade, even unilateral tariff cancellations on imports to the UK.

Trump has a pinched and paranoid vision of "America First". Yet Brexiteers nourish an expansive and open-minded dream of "Global Britain" signing major new deals with emerging market superpowers.

Trump is in the mould of his late 19th century predecessor, William McKinley, who proclaimed: "Protection is but the law of nature, the law of self-preservation, of self-development." Brexiteers such as Liam Fox, Boris Johnson and Michael Gove, by contrast, walk in the enlightened footsteps of John Bright, Richard Cobden and the Anti-Corn Law League.

But are Trump and the liberal Brexiteers as different as that rhetorical divergence suggest? As he unveiled his new tariffs on steel and aluminium last week, Trump articulated his philosophy on trade to Twitter.

"When a country is losing many billions of dollars on trade with virtually every country it does business with trade wars are good, and easy to win," he explained. "Example, when we are down $100bn with a certain country and they get cute, don't trade anymore - we win big. It's easy."

One can hear an echo of that "we can't possibly lose" perspective in the Brexiteers' misplaced confidence that, because the European Union has a trade in goods surplus with the UK, the Europeans will ultimately be desperate to sign a post-Brexit free trade deal.

"Within minutes of a vote for Brexit the CEOs of Mercedes, BMW, VW and Audi will be knocking down Chancellor Merkel's door demanding that there be no barriers to German access to the British market," the now Brexit Secretary, David Davis, famously predicted before the referendum.

What both the Brexiteers and Trump fail to understand is the nature of trade deficits. Trump is deluded to believe, as he clearly does, that a bilateral trade deficit is evidence of a country "losing" in trade and a surplus, correspondingly, evidence of "winning".

And the Brexiteers are deluded, albeit in a slightly different way, to believe we are, like a customer in a charity shop, somehow doing EU companies a favour in buying their exports - and that we could simply stop doing so without inflicting any harm on ourselves.

But, even accepting all that, Brexiteers would never advocate crude Trump-like tariffs, would they? Perhaps not. Yet leaving the EU single market and customs union are, nevertheless, inherently trade destroying policies for Britain; perhaps the most destructive since the Second World War.

No credible study has found any grounds for believing that hypothetical future trade deals between the UK and the likes of China and Australia could, arithmetically, compensate for leaving the EU's free trade institutions (which, let us remember, the Thatcher government helped to shape).

It's also worth delving a little more into the Trump position. On Twitter he embraces bellicose talk of a trade war. But speaking in Davos in January, the tone from Trump and his economic team was rather different. All they wanted, they said up in the Swiss Alps, was "fair trade", reform of a system "rigged" against America.

"The US is prepared to negotiate mutually beneficial bilateral trade agreements with all countries," Trump told delegates of the World Economic Forum.

This might get us closer to the underlying substance of the Trump position. What we have is a visceral rejection of multilateralism, or working in concert with other nations, as an equal, to achieve a mutually beneficial end. America will only negotiate with other countries one on one. For Trump, trade is really about power. It's an ideological view on the appropriate nature of international relations.

One of the most pointlessly destructive elements of Brexit when it comes to trade is that the UK will automatically fall out of the coverage of the 50 or so trade deals signed between the EU and a host of other countries, ranging from South Korea and Mexico to Chile and South Africa.

We will have to scramble to recreate those deals after 2019 merely to avoid damage to our own exporters who have come to rely on them. The net economic benefit of this upheaval is quite elusive.

Moreover, we might ask, what is the objection, if the Brexiteers feel the EU has not been proactive enough in seeking to strike new trade deals with emerging markets, to remaining in the bloc and pushing for change from within, working with similarly pro-free trade allies such as the Netherlands and Sweden?

The obvious answer is that liberal Brexiteers, like Trump, harbour a temperamental hostility to the very principle of multilateralism, even if it delivers the ends they purport to want. It's a hostility that overrides any rational cost-benefit judgement.

Working through the EU to enhance the export opportunities of our firms and reduce import costs for consumers would not enable these political narcissists to feel, on a personal level, that they had taken back control.

Despite their rhetoric, for liberal Brexiteers, leaving the EU is less about new trade opportunities, than power. And, as with Trump, the power in question is not really their country's but their own.

Ministers should stop appeasing obscurantist Tory backbenchers and publish their internal Brexit analysis

One would need to have been living under a rock not to know what the headline findings are from the Government’s internal economic modelling of Brexit scenarios.

All the outcomes – from departing with no trade deal, to staying in the single market – are projected to leave the British economy worse off relative to otherwise, according to last month’s well-publicised leak. So Brexit, according to the Government’s own modelling, will do economic damage to the UK.

Yet the Government refuses to publish the underlying research, even though ministers have been forced to agree to make the document available to MPs within the confines of Parliament. Apparently they believe publication would undermine the UK’s negotiating position with the rest of the European Union.

Why internal research which backs up what every other credible independent modelling exercise has found to be damaging is left to our imagination.

And, in fact, the real reason for the publication refusal was identified by Damian Green in his first interview since his resignation this week.

“There’s a great problem of politicians who won’t accept evidence,” he told the BBC. 

In other words, pro-Brexit ministers and the Brexit fundamentalists on the Tory backbenches don’t like the findings and so don’t want them to be released.

Green thinks his former ministerial colleagues should buck up and simply publish the work. “Let’s have this argument in public, that’s what democracies do,” he implored.

Perhaps the advice of technocratic experts is getting through. Did Green maybe hear Robert Chote, the head of the Government’s official spending watchdog, the Office for Budget Responsibility, who suggested earlier this month it had been a mistake to try to keep the work concealed in the first place.

Perhaps Green had an ear open when the Bank of England Governor, Mark Carney, at his most recent press conference likewise suggested the work should be released “so there’s an as informed a debate as possible.”

Yet does publication actually matter now, given we already know the bottom line results?

Beyond embarrassing those pro-Brexit ministers, who informed us that leaving the EU would be a great economic fillip for the UK, is there anything to be gained from it?

The answer is yes.

As Paul Johnson, director of the Institute for Fiscal Studies, argues in an article for Prospect magazine, it’s less the precise numbers produced by such modelling exercises themselves than the general picture that really matters.

And the general picture has been that the vast majority of qualified trade economists are confident the UK will grow more slowly outside the single market and customs unions due to it being, by definition, more difficult to export to our biggest trading partners.

“Although not quite 100 per cent certain, these sorts of claims aren’t far off,” Johnson explains. “The exact impacts, on the other hand, are highly uncertain. In public debate, the inevitable arguments about the exact number somehow end up clouding the solid general conclusion.”

His reference to the “exact impacts” represents a powerful reason for full publication of this work.

The Brexit minister Steve Baker, one of those politicians who has a problem accepting evidence, recently dismissed economic forecasts as “always wrong”.

And many people, including some high-profile journalists, seem to believe the stronger-than-expected performance of the UK economy since the June 2016 Brexit vote has borne out the truth of this claim.

Yet they have failed to grasp the crucial fact that all the long-term Brexit impact projections have been “conditional”. That means they are predicated on certain assumptions about the behaviour of the economy independent of the impact of the factor (leaving the EU) they are trying to model.

The actual path of the economy will almost certainly be different to those sketched out because lots of other unpredictable things are happening to our economy. For instance there may be stronger overseas demand for our exports as other countries experience an unanticipated boom, or perhaps, acting in the other direction, even weaker domestic productivity growth than feared. This can push overall GDP up or down relative to the conditional forecast.

But it’s a basic error to conclude from this aggregate divergence that the assessment of the impact of the factor being studied – Brexit – was wrong.

There is a world of difference between unconditional and conditional economic forecasts. Many people, even those who would be shocked at the suggestion they are unwilling to accept evidence, clearly need to be educated in that distinction.

But it’s hard to learn a lesson when ministers keep their civil servants’ modelling assumptions secret and when the basic nature of the forecast – conditional or unconditional – itself remains under lock and key.

And that’s why we should join Green in calling on ministers to stop appeasing obscurantist Tory backbenchers and get on with publishing this research in full.

UK companies are losing patience with the ideological fantasies of Brexiteers

Comparisons between politicians and business leaders are generally to be avoided.

But sometimes they can be instructive.

Imagine if a chief executive was explaining to her governing board how she planned to tackle a major looming economic threat to the company's profitability.

Imagine if she started her presentation with the words: "Close your eyes and envisage a new technology, which doesn't currently exist but which we very much hope will soon come along..."

How long would she be likely to remain in her job? Indeed. But standards appear to be somewhat lower in politics. Or at least different.

There seems to be confusion about the nature of the EU's custom union. Many commentators (and even some economists) talk about it as essentially a problem of tariffs: levies on goods as they cross borders. But this is only part of the story, and not the most important share.

The biggest economic hazard facing UK firms when we leave the EU customs union is not charges on imports and exports but disruptive new inspections and the effective severing of vital corporate supply chains.

According to a recent analysis by the Institute for Fiscal Studies, more than half of the UK's imports from the EU are "intermediate" goods and services. This means they are not for immediate consumption by households, but rather are used in the production processes of British firms. The intermediates share of UK exports to the EU is even higher, at almost 70 per cent.

The crucial point is that outside the EU customs union, this formerly free flow of goods between the UK and the EU would have to be subject to intrusive checks - checks for compliance with local safety standards and also checks that all the applicable levies have been paid.

Even if the UK agreed a comprehensive free trade deal with the rest of the EU which abolished all goods tariffs, inspections on standards compliance and checks for possession of the requisite tariff waivers would remain.

UK-based car manufacturers are extremely dependent on component imports from mainland Europe, with parts often delivered "just-in-time", and are, thus, highly financially vulnerable to any disruption to these supply chains. But the same also goes for a host of manufacturing sectors. This all applies, of course, to the border between Northern Ireland and the Republic, with the particular historic and political headache overlaid there.

That is why the director-general of the CBI, Carolyn Fairbairn, made an almost desperate plea this week for the Government to put evidence ahead of "ideology" and commit to a new customs union with the EU after the (hoped-for) Brexit transition phase ends in around 2021.

While this would not eliminate the need for all checks - Turkey has a customs union with the EU but its goods still have to be inspected when they enter Europe - it would be considerably less punitive for UK trading firms. "A practical, real-world answer" is Faribairn's description.

But ideology clearly doesn't like being put in the corner. Boris Johnson took to Twitter to slap down the CBI's recommendation, asserting: "Staying in the customs union means effectively staying in the EU: the EU is a customs union ... it means no new free trade deals, no new leading role in the WTO [World Trade Organisation]".

"I'm confident British business can profit from the new opportunities," he concluded, presumably while puffing out his chest.

Leave aside the typical Johnsonian sloppiness over some important detail (the CBI is suggesting the UK form "a" customs union with the EU, not remain in "the" existing customs union), his argument can be boiled down to the view that the pain of UK firms arising from this disruption will be swamped by the fantastic gains of new trade deals with non-EU countries that the UK will be liberated to sign by leaving the customs bloc.

Yet manufacturing firms are not so sanguine, which is precisely why they have been pressing the CBI to make its latest customs union recommendation to the Government. Incidentally, research by Monique Ebell of the National Institute of Economic and Social Research suggests the overall trade benefits for the UK of any new free trade deals with non-EU countries are likely to be underwhelming, certainly relative to the severe trade damage from leaving the single market and customs union. That's some actual evidence that firms might weigh against Johnson's indomitable personal faith.

Yet Johnson, among cabinet members, has no monopoly on wishful thinking. The Government's official white paper on the UK's future customs arrangements, released last August, addresses the issue of looming customs checks for British firms with little more than vague talk of "increased automation and better use of data".

Meanwhile, the Legatum Institute, a think tank that has a firm grip on the ear of the Brexit Secretary, David Davis, has even proposed that the job of patrolling the Irish border after Brexit could be delegated to "unmanned aerial vehicle assets" and "aerostats" instead of traditional customs offices. In other words: drones and airships.

The airborne technology that could perform such a job doesn't, of course, yet exist. But Legatum suggests "awarding a prize for technological solutions to incentivise the development of innovative solutions from the private sector, and universities". They are no doubt as confident as Johnson that something will turn up in time.

This truly is the voice of irresponsible ideology. Small wonder that UK exporters, who would actually have to trade in this new world, rather than merely fantasise about it, are losing their patience.