Britain's Prime Minister Theresa May, center, reacts to votes related to her Brexit deal in the House of Commons on Tuesday. (Jessica Taylor/British Parliament via AP)
Ian Dunt is the editor of Politics.co.uk, the author of "Brexit: What the Hell Happens Now?" and a host on the Remainiacs podcast.

On Tuesday, British Prime Minister Theresa May demanded that her party reject her own Brexit plan so she could go back to negotiations with the European Union and dismantle an agreement that her government reached with the continent, on an impossibly fast timeline, during talks that have already been ruled out. On every level, it is an insane way to behave. The British government is actively sabotaging the work it has spent the past two years completing and then doing a victory dance.

 The problems all lie with something called the Irish backstop. You wouldn’t know it, given how deranged the party has become about it, but it is a Conservative idea. Their problem was simple: They wanted two contradictory things. On the one hand, the Brexit campaign during the referendum promised to “take back control” from Brussels. That meant returning regulatory decision-making to London. But on the other, it promised that everything would continue as before, with no effect on trade. That is impossible, because as soon as you take back regulatory powers, you have delays on the border with Europe.

The whole issue with the border is based on the concept of trust. In the European Union, member states share laws, courts and enforcement procedures. They know that the rules on the slaughter of cattle, the electronic components of cars or the chemical compounds in children’s toys are all the same. They can take someone to court if something goes wrong, even if they’re in another country, because they have the same institutions. This creates trust. And that’s why goods cross over national borders freely, with no checks. 

That has been particularly crucial in Ireland. After years of conflict, peace was reached  in the ’90s on the basis of continued cooperation between the north and south of the island. And that meant, more than anything, an open border between the Republic of Ireland in the south and British Northern Ireland in the north.

But then Brexit came and blew it all to pieces. Instead of grappling with the hard choices the vote required, May pretended that Brexiteers could have everything they wanted: London would get back control of regulatory decisions. And the border with Ireland would stay open. The fact that these two promises were incompatible was never addressed. She just kept on pretending that it was all possible and that people should have greater faith. 

There was a weird, and very un-British, quasi-religious undercurrent to all this — a sense that things would work if you just believed in them hard enough. Also discernable were a hatred of practical judgment and a bubbling tide of chest-beating jingoistic nationalism. Brexit was a political project based on the idea that identity politics could answer technocratic questions. If the technocratic question keeps proving problematic, you just need to have more faith in your identity. It was like trying to unlock a door with a slice of bread. 

That culture has not changed since the 2016 referendum. In the past week alone, three interviews exhibited the kind of fevered puritanism that Brexit has triggered. Conservative Member of Parliament Mark Francois responded to a letter from the German CEO of Airbus, warning that the company might move its factories out of Britain, by tearing it up on live television and saying: “My father, Reginald Francois, was a D-Day veteran. He never submitted to bullying by any German; neither will his son.” A former trade minister, Digby Jones, claimed that negotiations are facing difficulties because “the Remainers and especially the establishment elite have set about sabotaging Brexit.” One Brexit supporter interviewed on the street by the BBC about warnings from retailers over supply chains insisted that it would “do the country good” to go without food.

For her first two years in power, May kept pace with this new political culture. She acted like everyone’s Brexit dreams would come true and no trade-offs would ever have to be made. And then, last summer, her Brexit strategy finally acknowledged reality.

This involved the Irish backstop. It was an insurance policy. It said that sure, Britain could look for ways to maintain an open border with Ireland while taking control of regulatory decision-making. But if that failed, which it would, Northern Ireland, at least, would have to lock into the E.U.’s regulatory infrastructure so that the E.U. would know that the rules on things like cattle slaughter, the electronic components of cars and the chemicals in children’s toys were all the same. This would allow the border to stay open, without the need for checks. In essence, it promised that if the fairy tales failed, reality would take over, on a strict timetable.

The plan was May’s baby. She negotiated it. She even demanded it be extended from Northern Ireland to the whole  United Kingdom. But it was just too much bleak practical reality for the Brexiteers. So when she brought it to the House of Commons almost three weeks ago, lawmakers smashed it into a million pieces, with a historic government defeat.

After she reeled for a couple of weeks, Tuesday night saw May finally regain some sort of initiative: She grabbed hold of an amendment floating around by Conservative lawmaker Graham Brady and tried to use it to her advantage. 

It was a very strange and pointless amendment. It said, in a not legally binding manner, that Parliament would back the Brexit deal if “alternative arrangements” were found for the backstop. What were these alternative arrangements? How do you promise to keep a border open while simultaneously not promising to keep a border open? Brady couldn’t say. Neither could the prime minister or any other member of her government. They had no idea what they were doing. They just needed some words, any words, that could win majority support in the Commons. The fact that the specific words they chose made no sense was an advantage: If the amendment had made sense, someone would have taken offense at its implications. This is the logic of fairy tale politics. The most common idea among Brexiteers is that they will use “high-tech solutions” to remove the need for checks at the border. But the technology they are wishing for does not exist anywhere on Earth. It is science fiction.

Not only did Brady’s proposition have no meaning, it was common knowledge before it was voted on that it could not be delivered. The E.U. has closed the talks on the withdrawal agreement. It has made it quite clear that they cannot be reopened. And even if they could, the backstop  took nearly two years to negotiate. There are only two months left before Britain leaves the E.U. That’s not enough time to do whatever it was lawmakers voted for Tuesday night.

That’s what made the debate so truly pitiful. It was a return to the world of fairy tales and hallucinations, of the kind of quasi-religious nationalist politics that have fueled the Brexit project from the start. British politicians were confronted with reality and given a chance to fix the problems with Brexit instead of pretending there weren’t any, and they once again fled back into mythmaking.

The country is now on the verge of disaster. On March 29, unless something is done, Britain will fall out the European Union without a deal. That will affect every aspect of the economy. It’s likely to block cargo  at the border; pulverize agricultural exports; trigger shortages of food, medicine and radioactive isotopes; spark employment chaos by suddenly canceling the mutual recognition of qualifications between British and European institutions; halt the legal basis for data transfer overnight; and lead to massive and sudden flows of immigration in both directions. The list goes on and on. There is no part of society that is unaffected. And yet not only does the British political class not seem to understand the consequences of what it is doing, it is lost in populist fantasies instead of addressing the cold reality.

Britain is one of the richest and most advanced democracies in the world. It is currently locked in a room, babbling away to itself hysterically while threatening to blow its own kneecaps off. This is what nationalist populism does to a country. 

Twitter: @IanDunt

Read more from Outlook:

Brexit will make things worse. Is that why people voted for it?

British millennials like me are the real losers in the Brexit vote

Five myths about Brexit

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