The BBC is a pillar of civilisation. No wonder populists want to destroy it

The most alarming feature of our times is the disintegration of a shared belief in the values and principles of the European Enlightenment. They were never shouted from the hilltops, but were key to what we used to hold in common, and their collapse was a chief cause of Brexit. Unless they are quickly rediscovered and seen as a point around which to reunite, the BBC will now fall as well.

Enlightenment values come in an interconnected bundle. First and foremost is the idea that there are objective truths and an accompanying public realm, held for all citizens, in which these truths can be tried and tested by argument, evidence and reason. It follows that there must be freedom to think and freely express oneself – otherwise no argument is possible. Science and fact will thus trump partisan ideology and superstition.

This creates a public interest, expressed by government, that is held to account by equal citizens who can turn to law and independent judges to protect them. Thus the EU’s treaties, and thus the BBC’s public service obligation to educate, impartially inform and entertain every citizen. It is a cornerstone of the public realm.

Rightwing populism confounds these principles. Conceptually, it holds, the public realm is a fraud: there is only an aggregation of individuals whose fate is to pursue their own interest. There can be no resolution or common ground achieved by argument; my truth is the only truth. Impartiality and public service are myths. Science can only be tolerated if it delivers conclusions with which I agree. Law and judges who get in the way of the popular will should be brushed aside. Only my views should be freely expressed. Christian faith is inherently superior to any other, which can be mocked and derided.

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The EU with its acquis communautaire celebrating the rule of law is anathema. So, too, is the BBC – an Enlightenment stronghold daring to pretend it can embody public service broadcasting and an imagined impartiality which disguises that it is the natural enemy of rightwing Toryism with its anti-Enlightenment roots. It is the populist libertarian values of Fox News or Britain’s rightwing press – intolerant of difference – that are inherently those the right should champion.

Populists of the left hold mirror-image beliefs. There is not a public realm; “publicness” can only be expressed in a socialist collective in which notions of public and private are dissolved. The public interest can only be the socialist interest. Socialist law is founded on socialist jurisprudence. Elections are essentially only useful to validate one socialist choice. Thus Momentum’s leader, Jon Lansman, can organise a ballot to test his members’ views in which only one candidate can be voted for – Rebecca Long-Bailey. Thus Jeremy Corbyn’s hostility to an EU whose Enlightenment treaties might obstruct the creation of a socialist collective, and his instinctive distrust of a BBC whose commitment to truth-telling will include reporting antisemitism in the Labour party.

There was no one reason why the EU referendum was lost, but a major cause was that liberal Conservatives and the soft left of the Labour party could not jointly come together passionately to express their joint commitment to the Enlightenment principles on which not only the EU – but Britain – is founded. If David Cameron had been more prepared to take on his Brexit right and had Labour been led by a figure from the Enlightenment left, a common platform might have been created. But neither precondition held.

My fear now is that exactly the same forces are going to engulf the BBC. If it is forced to fund the £745m annual cost of free licences for the over-75s – the deal forced on it by George Osborne in 2015 – swingeing cuts will follow. Public service broadcasting, already under intense pressure, will look second- or even third-best. Popular support will ebb away. And though I’d like the licence fee arrangement to hold, the BBC won’t be “freed” to become subscription-based, a second-best option, in the charter review of 2027: that might be too successful. Instead, it will be kept on a tight leash, with neither mainstream liberal Tories, nor the best in a marginalised, gravely weakened Labour party having the political heft or inner conviction to save it.

David Clementi, the BBC chairman, was absolutely right last week to ask the director general, Tony Hall, to step down at least two years earlier than he planned. Hall’s love for the BBC is total, but the leader who agreed the fatally damaging deal cannot now be the leader who must try to muster the forces to change it. Boris Johnson, already trimming on a hard Brexit because it is so damaging to the Midlands and northern constituencies he has so recently won, has got to throw his Brexit right some red meat. Insisting that the BBC “cough up”, as he has said, is an easy ploy.

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The new director general, backed by the BBC board, is going to have to create a political mood where that becomes a politically impossible ploy. Of course there are the usual cards – think Blue Planet or Fleabag – and as many hand-wringing, kindly articles as possible urging us to think what might be lost if the BBC becomes a shrunken shell. But success will demand much more. The BBC has to get on the front foot, backed by staff and audiences alike, and make the case that it, and the network of public service broadcasters it anchors, is one of the cornerstones of our civilisation.

It doesn’t have to use the word Enlightenment but it is those values – impartiality, public interest, fairness, tolerance, good humour – that need to be carried forward. It has to say that despite the backlog of damaging claims over unequal pay, its processes now mean its standards on remuneration are the best in the public sector – and challenge its detractors to match it. (Full disclosure: last year, I wrote a report for the BBC on public service transparency.)

Borrowing Yeats, we certainly live in a time when the worst are full of passionate intensity; but now is the moment for the best to recover their conviction and to dispel impending anarchy. Time for the Enlightenment centre to hold.

• Will Hutton is an Observer columnist