The loudest sound in Birmingham was of doors being slammed shut | Andrew Rawnsley

The Tories are hurtling towards a hard Brexit and a riven Labour party is no position to stop them

Seeking sustenance in a Brummie cafe to get me through the Tory conference, I heard myself request a full English Brexit. Thats what it does to your head: several days of close confinement with Conservatives salivating over departure from the European Union.

Back in the conference hall, the full English Brexit was being served up by Theresa May and all the mini-Mays in the cabinet as they sought to satisfy the audiences appetite for the starkest form of rupture with our partners of the past four decades. There are several possible ways of exiting the EU. They range from amicable separation to bitter divorce. The Tory gathering in Birmingham set Britain on a course that leads to the most turbulent, disruptive and hazardous form of departure. It was the working assumption of all the cabinet ministers I spoke to, and this was so regardless of which side they took during the referendum, that it is now near inevitable that Britain will cease to be a member of the single market. Among those Tories who have always yearned for that outcome, I found them talking as if it was a given. Even more significantly, ministers who would once have recoiled in horror from that prospect now sound resigned to it.

This is hugely significant and how we got to this point needs some explanation. In June, it was not a given that Britain would do Brexit the hard way. Out had won, but only narrowly. There was much room for interpretation of what that meant. There was quite a lot of talk from leading Outers about needing to respect the 48% who voted the other way. Once the forces of Remain had recovered from the shock of their defeat, they initially remustered around the cause of preserving British membership of the single market and with it the trade and investment on which so many livelihoods depend. They could cite the Tory partys election manifesto. This had clearly suggested that, even if Britain voted to leave the EU, a Conservative government would sustain membership of the single market. The manifesto promised: We are clear about what we want from Europe. We say: yes to the Single Market. That, Remainers declared, was the trench where they would dig in.

That trench is still there, but I found very few people left defending it in Birmingham. The Tories are plunging towards hard Brexit and a riven Labour party is not in a fit condition to stop them. After an initial period of complacency, investors are waking up to the prospect that Britain could lurch out of the EU without reliable access to her most important markets. The more loudly her activists cheered Mrs May, the faster came the plunge in the pound. By the end of the week, sterling had dropped so vertiginously that one pound didnt buy one euro at bureaux de change. As it has become clearer that Britains government is tilting towards the Full Monty Brexit, so European leaders have hardened their language about the penalty that will entail.

Why has this happened? A large part of the explanation is Mrs May and how she is choosing to resolve the paradox of being a prime minister tasked by the voters to deliver an outcome that she campaigned against. Many of the hardline Tory Brexiters were highly wary when she first moved into Number 10 because she had been a Remainer, albeit a near-invisible one, during the referendum campaign. Now the Brexiters speak of Mrs May in glowing terms. It turns out that having a Remainer as prime minister has worked perfectly for us, one remarked to me. She has to keep proving to us and the party that she is serious.

She threw them three big lumps of meat. One of those announcements was really spin disguised as meat. Her Great Repeal Act will in reality transfer EU law into British law, to then be removed or amended at a later date. Her more substantial announcement was that she would trigger article 50, the formal notification to the EU that Britain wants a divorce, no later than March next year. This creates an unforgiving timetable for what will be a horrendously complex and fraught negotiation.

Even some of the Brexiters in the cabinet are starting to sober up to the reality of it. To describe the inundation of papers on the subject that he is consuming, one minister adopted an Americanism and told me it was like drinking from a fire hydrant.

That negotiation will not be made easier by the prime ministers third, and most significant, act. That was to set a firm face against trying to find any accommodation with EU countries over freedom of movement. We are not leaving the European Union only to give up control of immigration again, she declared. One of her cabinet confirmed to me that they plan to approach the negotiations by telling the EU that freedom of movement is simply not on the table; they only want to talk about trade. If you believe that the Out vote was powered by opposition to migration, then the only form of Brexit that respects the referendum result is a mode of departure that ends freedom of movement. This position has a logic to it and some of the recanting Tory Remainers contend that this logic is too powerful for them to argue with it. Resistance, they say, is futile. It is impossible to reconcile rejecting freedom of movement and the jurisdiction of the European court of justice with continued membership of the single market. So Britain will be left to gamble on trying to get some sort of tariff deal with EU countries at a time when they are in no mood to do us any favours.

Stockholm Syndrome describes how some hostages become traumatically bonded with their kidnappers. Remainers in the cabinet often sounded like they were the psychological captives of the Brexiters. Amber Rudd, a liberal Tory who was a star of the Remain campaign, was one of the ministers who made a hostage-video sort of speech to the conference. The home secretary announced that companies would be forced to declare how many foreigners they employed, as if attracting skilled people from abroad was a mark of shame. In her setpiece at the end of the conference, Mrs May denounced citizens of nowhere. That was a clever applause line with unclever implications for a country that thrives by attracting overseas talent and investment. It is this that will be noted by the rest of the world, not fatuous rhetoric about Britain going global. The conference resounded to the slam of doors being shut.

There were a few voices of resistance. One was the effervescently gobby former minister Anna Soubry. Another was the former cabinet minister Nicky Morgan. They stood out so much because those prepared to argue openly for a softer Brexit were so thin on the ground in Birmingham. Tory resistance to hard Brexit has been badly weakened by what has been happening in the Labour party since the referendum. In its immediate aftermath, Labour MPs declared that they would battle to preserve membership of the single market. Then they examined the vote in their partys traditional heartlands in Wales, the north of England and the Midlands and grew terrified by the strength of the Out vote there.

The Labour conference in Liverpool was notable for the number of prominent MPs from its centrist wing declaring they could no longer defend unrestricted freedom of movement. Jeremy Corbyn has another position again. He is hostile to the single market but in favour of unlimited migration. The net result is that the Tory soft Brexiters do not think that they can rely on support from the main opposition party.

Business and the City are becoming increasingly agitated that Brexit will not be the soft landing they hoped for. Representatives of manufacturers at the conference spoke of becoming more depressed by the day. But the mood of the times is not sympathetic to business arguments. It was striking to witness a Tory conference eagerly applaud a Tory prime minister lacerating corporate Britain. Some Tories say publicly, and more will say privately, they are willing to sacrifice some prosperity if that is the price of curbing immigration. This made it especially ironic that the Tories met in Birmingham, a melting-pot city whose prosperity was built on entrepreneurship and trade. Never has the Conservative party sounded less like a friend of business. Never has the Conservative party sounded more hostile to liberal free markets. Were the Labour party under a different form of management, the Tories might be more nervous of alienating business by taking the hard route to Brexit. But not in a century of Sundays are the CBI and the City going to ally themselves with Mr Corbyn.

Free-market liberals still have some champions in government, notably at the Treasury, which thinks the economic impact of a hard Brexit will be severe and long lasting. Philip Hammond, the chancellor, told the conference that the referendum result was not a vote to make Britain poorer. That he would not have said unless he feared his colleagues are pushing in a direction that will leave Britain very much the poorer. The chancellor sounded like a man losing the battle. Lost it will be unless he finds some more friends and quick.

Nicky Morgan, the former education secretary, was one of few Tories prepared to call for a softer Brexit. Photograph: Steve Back/Barcroft Images

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