London banks are weighing up the charms of Frankfurt or Paris (Frankfurt is winning, London will be the loser). Goldman Sachs is shifting jobs from Britain. Airlines are being lured abroad, not for a holiday, but for good. Even Icelandic banks are now considered a safe bet for British businesses to move to after Brexit.

But the right-wing press ignores the impending crash, cheering on Theresa May as she hurtles towards a cliff, driving her Brexit battle bus with a blindfold. Many passengers are cheerfully oblivious, lured into believing that the Conservative Brexit government can deliver what it has promised: to secure all the trading rights that Britain currently enjoys, just without those pesky obligations that go with EU membership such as freedom of movement and contributing to the EU budget.

Anyone who dares to nudge a few facts into the debate are denounced (the BBC is the latest, duffed up by 70 Tory MPs.) So I am aware the jeering and jingoism will be loud today when I introduce a Ten-Minute Rule Bill in the Commons that aims to give the people the final say on the Brexit deal. I am, apparently, the “Remoaner in Chief”.

What might be harder to hear amid the interventions will be any concrete Government plans that will deliver the deal it has promised.

Labour voted for Brexit and Jeremy Corbyn has never had his heart in holding Conservative Brexit ministers to account for one of the most horrific wounds inflicted by a post-war British government on its own people. So in the absence of a functioning Official Opposition, I will provide the questioning, forensic challenge that any government needs.

Theresa May pledges prosperity to whole of UK

This is not about “blocking Brexit”, it’s about holding Theresa May to account for her choices – notably her stated decision to take Britain out of the world’s largest market, regardless of whether any new trading arrangements are in place. To question that is not disloyal: disloyalty to the British people would be to stay silent, failing to warn how that could bash living standards.

Few voted to leave the single market. That was not on the ballot paper. Most prominent Brexiteers expressly said that Britain could have membership of the market and new trade deals, as well as immigration controls. As a vision of an alternative reality it challenges the imagination of JK Rowling.

No wonder Conservative MPs are determined to silence those of us that want to explain precisely what they are about to unleash. They complain that the BBC is unable to break out of “pre-referendum pessimism and accept new facts”.

Presumably the MPs did not mean new facts that inflation is up to 2.3 per cent this week, breaking official targets, driven by a Brexit squeeze of a falling pound and rising import costs. Or is even the Office of National Statistics, which produced the inflation figures, peddling fake news?

Germany has replaced Britain as Europe’s fasted growing economy, investment is down and companies are relocating. But to question it is to be a quisling: truly, the definition of patriotism has been turned upside down, when those who love their country and fight to protect its interests are torn into by some increasingly sinister voices.

Conservatives can try to bully the BBC into changing its news coverage, but they won’t change the economic facts that spring from Theresa May’s decision to leave the single market. The Tories have lost the right to call themselves the party of business, and they are losing the right to call themselves patriots.

Senior figures are finding their voice. Tony Blair and Michael Heseltine have joined the likes of me and Nick Clegg in speaking out against an increasingly authoritarian approach that denies all opposition.

Nick Clegg accuses ministers of "procedural machismo"

In discussions Nick Clegg and I have had with EU prime ministers, it is clear that if the Prime Minister was big enough to admit now that she simply hadn’t appreciated how fiendishly complex Brexit would be, and that it had all been a horrible mistake, but that she needed a deal on immigration to satisfy the hard right wing of her party, she would get such a deal.

To be clear, I believe in free movement, but if “taking back control” while presumably retaining some semblance of economic stability is still the Tory aim, it is bizarre that Theresa May is working against her own desired outcome.

Instead, she wants to leave the EU no matter what the harm. Not even Margaret Thatcher would be that blinkered. Theresa May is screwing her eyes tight and hoping for the best. But the cliff is drawing closer, and the Brexit bus is speeding up.