With apologies to turtles and rocks, Brexit is myths all the way down.

Its central thesis – that the UK can turn on its heel and thrive without the EU – has proven to be a myth. According to UBS, the UK has already lost 2% of GDP due to Brexit, and it hasn’t even happened yet.

Its supporting economic argument – that the UK can replace advantageous arrangements with the EU with a free trade deal, and make up any shortfall by creating new agreements with other nations – is a myth. The government’s Chequers proposals are dead in the water and we are hurtling towards a No Deal exit.

And I need not go into detail on the many other fanciful promises that were made during the referendum – many of which were disavowed almost as soon as the result became clear. They were clearly myths, too.

Beyond the referendum itself, there are other myths on which Brexit rests. Chief among them is the British nationalist myth: we’re exceptional, and we are capable of standing alone in the world, and that great long-lived myth of World War II – the oft-debunked and totally discredited ‘Blitz spirit’ – will see us through anything.

Today, the former governor of the Bank of England, Mervyn King, has added his own contribution to the list of Brexit myths. In widely reported comments to the BBC, he claimed that the government’s ‘lack of preparation’ for Brexit had ‘beggared belief’, and that news of food and medicine stockpiling

‘doesn’t tell us anything about whether the policy of staying in the EU is good or bad, it tells us everything about the incompetence of the preparation of it’.

Mervyn King (IMF Staff Photograph/Stephen Jaffe)

King is a prominent supporter of Brexit. Yet Brexit as promised to the people who voted for it is an impossibility. So it’s in his interests to change the conversation. As the quotes above show, the way he and others are trying to do this is to blame the failure of Brexit on incompetence rather than fantasy. Labour have been particularly fond of this narrative, with their central campaigning theme on Brexit being (to paraphrase) ‘if only you’d get shot of the rubbish Tories, we’d take over negotiations and everything would work out great’.

Remainers need to resist this narrative. It is a myth as dangerous as any proposed during the referendum campaign. Allowing people like King to paint what is happening in the UK as mere ‘incompetence’ is to misallocate blame. Instead, we must keep reminding people that no politician and no government can ever deliver Brexit as it was presented to the people who voted for it.

Without consistently making this point, we will fall into the trap that King and his allies are setting. It’s the same dogmatic approach to an ideology that you see with communism – that it has never been done ‘properly’. As if on cue, King’s comments followed on the heels of Boris Johnson’s latest absurd missive in the Daily Telegraph, in which he claims that the current state of things shows ‘not that we have failed, but that we have not even tried’.

It’s not enough to suggest, limply, that a more intelligent or competent government would handle this better. In the context of the referendum campaign and the myths that won it (to say nothing of the illegality), there was no realistic political course for a Conservative Prime Minister to chart.

No, instead, it is time to come clean and say, badly paraphrasing the great European Winston Churchill, that Brexit is a fantasy, wrapped in an impossibility, inside a dream. It’s myths all the way down, and it’s time for the UK to wake up.