This essay, on the shallowness of cultural and political debate, was my Observer column this week. (The column included also a short piece on Home Office plans for asylum seekers.) It was published on 4 October 2020, under the headline “Welcome to Flatland, where shallow appeal ousts substance and reason”.

Four international art galleries decide to “postpone” a controversial exhibition. Donald Trump and Joe Biden take part in what has aptly been called a “shitshow” of a presidential election debate. Celebrity activist Laurence Fox launches a political movement to reclaim “British values”. On the surface, these disparate events have nothing in common. However, that is also what they have in common – each shows how art and politics are now lived on the surface with little consideration of depth or meaning.

The four galleries – Tate Modern in London, Washington’s National Gallery of Art, the Museum of Fine Arts in Boston and Houston’s Museum of Fine Arts – decided to postpone, until 2024, a long awaited show by the artist Philip Guston because the Black Lives Matter movement has shown the need for “the powerful message of social and racial justice that is at the centre of Philip Guston’s work… [to] be more clearly interpreted”.

But why should the galleries do all the “interpreting”? Art, after all, is about engagement – the same painting, novel, play or film can have many readings. That’s one reason why art can be so thrilling. We live in a world, though, in which many insist that there can only be one way of interpreting contentious issues, whether racial justice or trans rights.

The other side of the denial of independent interpretation is the tyranny of the literal: that what’s on the surface is all that matters, that the external form cannot be distinguished from deeper meaning. The problem with Guston’s paintings, for the show’s curators, seems to be that many depict the Klu Klux Klan in white hoods. Guston was unswervingly anti-racist – one of his works, The Studio, shows him painting in a hood, to illustrate what he saw as his own complicity in white supremacy. If any artist fits the current political mood, it’s Guston.

The galleries, however, seem to think it impossible for audiences to be able, without their expert aid, to tell the difference between racism and a critique of racism. So the cultural gatekeepers have taken it upon themselves both to interpret the paintings for us in the right way and to protect us from being upset or discomfited.

A world in which we fetishise surface appearance, in which people cannot be trusted with their own interpretations and in which we fear being offended or unsettled, leads also to the spectacle that was the US presidential election debate. It was less a forum for politics than a form of real-life trolling. The character of the debate was clearly shaped by Trump’s needs and his insistence on dragging politics into the gutter. But it also exposed in a particularly extreme form an aspect of politics that extends well beyond Trump. Politicians today seem too often to be more interested in feeding the outrage machine than in illuminating debate, preferring slogans to reasoned argument, dismissing scrutiny as “partisanship” and treating truth as if it were a form of entertainment.

And then we have Laurence Fox’s Reclaim, “a new political movement that promises to make our future a shared endeavour, not a divisive one”, the seeming opposite of the Trump approach. It has apparently already received £5m in funding.

A political movement, though, needs, well, politics. And on this, we have so far heard nothing. Where does Reclaim stand on the question of “offshoring” asylum seekers? On whether people should be fined for breaking self-isolation rules? On how far we should be able to offend others?

These are all divisive issues because politics is, by definition, divisive. It demands that people take sides on contentious questions. The pretence that it’s possible to have politics that is not divisive is a demand that we paper over the rifts and inequalities that rend society, a stance that can only favour those with privilege and power. The problem today is not that societies are polarised, but, rather, that they are polarised less by ideology than by identity and that tribalism has become an end in itself.

Without a modicum of politeness, or a willingness to listen to others, or an openness to scrutiny of one’s own beliefs, we inevitably end up with a “shitshow”. But, important though they are, these are only means to an end, not ends in themselves. A party with no policies or content apart from “Why can’t we all be nice to each other?” is as much about skimming the surface, of refusing to engage with depth, as Trump’s trolling or the galleries’ contempt for their audience.

From art to politics, this is increasingly a world lived on the surface, abjuring any attempt to engage with depth or content. Welcome to Flatland.