Jeremy Corbyn became misty-eyed today on stage at the Royal College of Nursing, declaring:

‘Nye Bevan once said of the NHS:

“It will last only as long as there’s folk with faith left to fight for it.”

Be in no doubt that there are those folk.

I am one of them.’

How prophetic Bevan was – foreseeing the inevitable 24 hours/one week/two months (delete as appropriate) to save the NHS from destruction by the evil Tories. The architect of the health service predicted that the hour would come when it would need a champion, and lo, Corbyn has stepped forward to answer his call.

Except, inconveniently, there wasn’t any such call. Bevan never said those fine words.

An actor portraying Bevan did say them, in 1997, in a BBC television play about him called Food For Ravens, by the Marxist playwright Trevor Griffiths. You can find the whole film on YouTube, but here’s the relevant moment in which the actor, whom Corbyn appears to have mistaken for the real Bevan, delivers the line:

It’s quite fitting that Corbyn’s pitch on the NHS revolves not around a fact, but around a romanticised fictional account of the health service’s history. He is the apex of Labour’s deployment of the NHS as a trump card (or perhaps Trump card, given the fake news element of his speech). Bevan’s supposed prophecy is all-too convenient, because it was invented as a left-wing political narrative for a 1990s audience.

Traditionally, healthcare is not the topic chosen by Labour when it is on the front foot – rather, it is a mountain fastness to which they retreat when at their weakest. If all else fails to win over voters, they can at least cash in the credit of the folk memory of Bevan’s gift to the British people.

Except the power of even that tactic appears to be wearing off. Partly that’s due to endlessly crying wolf – time and again they have claimed that the abolition of the service is imminent under Tory government, and yet it has somehow survived 42 years of Conservative Prime Ministers since its creation. Partly, I suspect, it’s because the creation of the NHS, and the situation it replaced, are passing out of living memory. Specific to this election, of course, is the fact that even when Corbyn says something they agree with in theory, voters still tend to distrust him.

Under the pressure of those combined factors, the argument has worn so thin that it seems to have little traction any more beyond a core vote who already bitterly oppose the Conservative Party. In a variety of polls, the Labour lead on the NHS has been far lower than seen in the past, and earlier this year Opinium even found a Conservative lead in who could be trusted to manage it better (even though in the same poll they had scathing views of current health service performance).

Ultimately, whether voters buy Corbyn’s message on the NHS comes down to trust. They no longer seem to trust Labour’s message that the NHS will be destroyed unless Labour are elected. They don’t appear to trust that Corbyn and his colleagues are competent enough to run the NHS. And the Conservative riposte to all this rests on another issue of trust – the question of whether anyone can trust that a Labour government wouldn’t wreck the economy, undermining the tax base on which the NHS depends.