If you want to deceive the French public, you pose as an intellectual. In England, you pose as a character. Like a criminal on a witness protection programme, the ham actor who plays upper-class roles avoids the accountability that prevents democratic life degenerating into the feast of fools we see around us.

Brexit has as much been a failure of British journalism as British politics. The basic questions have not been asked. You promised the electorate a trade deal with the EU should be the easiest in history. You said the German car industry would force Merkel to capitulate. Are you a fool or a liar or both?

When the honourable exceptions have been listed, the British media have not held politicians to account or followed stories regardless of the consequences. Largely liberal broadcasters have so overcompensated they’ve forgotten why they went into journalism in the first place. They believe a 52-48 majority has freed them from the duty to scrutinise, regardless of whether – and this is the critical point – the 17.4 million who voted leave want them to or not.

Then there’s the undeniable fact that privileged journalists, like their political counterparts, subconsciously know they don’t have skin in the game and will not suffer the fate of farmers, car workers and aviation engineers. Standing above all these, however, has been a refusal to reveal the menace behind the masks of the right’s character actors. Nigel Farage plays the old English hearty full of cakes and ale. Boris Johnson is Billy Bunter with a smattering of Latin. Jacob Rees-Mogg poses as an Edwardian lawyer calmly laying out the facts. In short, Brexit is being pushed towards its miserable conclusion by men who raided the fancy-dress box for traditional robes.

Tackling them becomes the equivalent of cross-examining the Queen about her sex life

They get away with it because the old British ruling class never quite discredited itself. Every other major European country was ruled by fascists and communists in the 20th century and suffered occupation and collaboration. In Britain, it is still possible to adopt the mannerisms of the old elite and not be treated with the scorn and incomprehension a modern caricature of a Prussian general would receive in contemporary Germany.

I could go on about the depth of the chasm that separates image from truth. There is nothing remotely amiable about Johnson, for instance. “Everybody likes him except the people who know him”, as his fellow London Tory Steve Norris succinctly put it.

But the point that is rarely made is that once a character is established in England they become close to being a national treasure. Tackling them becomes the equivalent of cross-examining the Queen about her sex life.

Describe Farage as “a far-right politician” and you are met with protests and not only from the far right and its media supporters. Not a fascist or even a racist – at least not an overt racist – but a member of the transatlantic far right through his connections with Donald Trump and Steve Bannon and the European far right through his links with Matteo Salvini and Viktor Orbán.

What else should you call him? Farage is not a patriotic conservative who opposes Britain’s enemies, as his support for Vladimir Putin shows. Johnson in turn is not a traditional conservative who promotes enterprise, as his cry of “fuck business” proves. Indeed, Johnson and Michael Gove’s Vote Leave campaign began with a pre-emptive attack on the CBI, to discredit its warnings about dangers of Brexit to the economy. They aren’t conservatives, they are far-rightists. Why is it so hard to admit that we are no different from any other country caught in nationalist backlash?

‘There is nothing amiable about Boris Johnson’, pictured at the 2018 Conservative party conference. Photograph: James Gourley/Rex/Shutterstock

Britain’s privileged history explains the denial in part. We are a moderate island, runs the national myth, extremism happens over the water and far away. But the refusal to tear the masks away matters more. I have never seen a television broadcaster hold Farage to account for his blatant misrepresentations of the consequences of no deal.

The BBC could barely bring itself to cover his and his financial backers’ links to the Russian embassy. Journalists call Johnson “Boris”, as if he were a pal entitled to mates’ rates they would never grant a stranger. And when Eddie Mair, then of the BBC, did his job and subjected him to a tough interview in 2017, what would have been a routine occurrence in a healthy democracy caused a sensation.

Every slippery politician is looking for the same chummy consideration. Supporters of the Labour leader are trying to establish him as “Jeremy” rather than “Corbyn” or “Mr Corbyn”, to quote the most egregious example. Politicians become journalists and journalists become politicians, as the firewalls of democracy burn down. You don’t have to be famous to enjoy protection. Claire Fox, of Radio 4’s The Moral Maze, is inevitably one of the most immoral people in public life. She and her Revolutionary Communist party sect have covered up war crimes against Bosnian Muslims, justified IRA murders of civilians and defended child porn. Only when she stood for Farage’s party this month did most voters learn of her dark past. Why was it never mentioned in her hundreds of appearances on the BBC? The question answers itself. The BBC will not apply the same standards to its “talent” as it applies to others.

The week after the media personalities Johnson and Gove triumphed in the 2016 Brexit referendum I wrote: “If you think rule by professional politicians is bad, wait until journalist politicians take over.” Now you know the consequences: a country that cannot leave the EU or stay in. A country that can address no other issue but Brexit, but cannot resolve Brexit either. A country where no one who campaigned for Brexit will take responsibility for it. For all their aping of the manners of the Victorian and Churchillian establishments, the characters who have taken over the British right have not provided us with a ruling class but a ruling chaos.

• Nick Cohen is an Observer columnist