It has become a cliche of general election campaigns to claim the NHS is in danger – such a cliche that, so far, no party has yet made it in 2017. Yet it might be truer than it has ever been. The health service is under greater financial strain than it has been in its 69-year history. Targets like A&E waiting time limits, introduced by Tony Blair to drive improvements in the service, are being downgraded, and increasingly missed. A survey by the King’s Fund released on Thursday finds less than one in 10 finance directors confident that by September they’ll meet the target of 90% of patients being seen within four hours. In the final quarter of last year, more than 26,000 cancer patients waited more than three months for treatment. Annual accounts that the government has refused to release until after the election suggest that last year hospital trusts chalked up debts of £700m, despite one-off gains from land and property sales. There is a shortage of GPs, hospital doctors and nurses which will be exacerbated by any post-Brexit immigration controls that limit the ability to recruit from the rest of the EU. And none of the main parties has made the commitment to the long-term budget growth that every independent thinktank believes is necessary.

What the NHS needs is a serious, informed conversation about how much as a country we are prepared to pay in order to maintain the free, universal healthcare system to which we are all committed. It should be underpinned – as the manifestos of Labour and the Liberal Democrats both hint – by some kind of independent body, along the lines of the Office for Budget Responsibility, to act impartially on expert evidence. It would end the claim and counter-claim caused by NHS manifesto commitments that are as opaque and hard to compare as the results of an online search for car insurance. It wouldn’t take the politics out of the debate – how to spend taxpayers’ money is the essence of politics – but it would give it a sensible basis in evidence.

Voters tell pollsters that the NHS is one of the national institutions they most value and also most fear for. The public, according to pollsters, say they are prepared to pay higher taxes to fund hospitals and employ more doctors. Yet none of the main parties has pledged a big enough increase over the lifetime of the next parliament to allow medical care to keep pace with the pressure of an ageing and growing population. Labour comes closest, according to the IFS, promising what amounts to a 2% increase year on year; the Lib Dems’ penny on income tax would equate, measured in similar terms, to a 1.4% increase; and the Conservatives’ commitments work out at 1.2% a year – well below the 4% most experts think necessary. All three proposals mean per capita spending on health beginning to fall. On Nuffield Trust analysis, they mean allocating a slightly declining share of GDP when it needs to rise steadily just to keep pace with demand.

Yet this election does mark a watershed. One way or another, the politicians have signed up to a different way of organising healthcare that offers the chance of a more rational approach to the health service and the health of the nation. A 25-year experiment in trying to replicate market forces, which began with Ken Clarke’s internal market in the early 1990s, is being quietly dropped. So, in practice, are many of the provisions of Andrew Lansley’s disastrous and hugely costly Health and Social Care Act. Instead sustainable transformation plans, locally led reconfigurations to develop more joined-up hospital and care provisions, are being developed. There are vestiges of the market, but now place and outcome are being developed as the measure of success.

Labour is right to call for more public engagement in decisions that could mean closures of valued local services. But that needs reliable, accessible facts that could inform a proper debate about the future of a treasured institution.