There is one policy in the Conservative leadership debate that is exposing both candidates’ flaws. It’s the same policy that most politicians have failed to get to grips with, and that has dogged successive governments. And no, it’s not Brexit.

Social care has become an unlikely talking point in the race to become prime minister. An unsexy, difficult, expensive subject, it’s seen as a risky issue for politicians to touch at campaign time. Labour’s 2010 proposal to tax people’s estates after they die was swiftly labelled a “Death Tax”, and the Tories’ 2017 plan to include the value of people’s homes in means-testing for home care marred their election campaign after being christened a “Dementia Tax”.

However, the funding gap is now so vast (estimated to reach £3.6bn by 2025), the cuts so deep (public funding declined in real terms by 13 per cent from 2009/10-2015/16), and people so desperate (14 per cent of the over-65 population suffered an unmet care need last year), that even our most distracted politicians are being forced to mention it.

Both Jeremy Hunt and Boris Johnson have been confronted with the subject of social care in their leadership campaigns. Neither, clearly, gets it.

Hunt has made the spectacularly too-little-too-late admission that social care cuts went too far when he was health secretary and hospital beds were taken up by people who didn’t have adequate care at home to return to.

His proposal is for a personal insurance-style opt-out system that encourages people to save early on for social care, plus a vague promise of an undisclosed increase in council funding, and some guff about incentivising different generations of families to live together and care for their elderly relatives.

The former approach, though it’s been touted as one of the funding options for a while, is a non-starter according to the House of Lords Economics Committee’s recent report, which took evidence from the pensions and insurance industry.

“I confess I started off thinking myself, if you had a cap on expenditure on care, that would become insurable and could be part of a pension or insurance scheme,” says Michael Forsyth, the peer who chairs the committee and describes himself as a “Thatcherite Tory”.

“But the evidence we got was this will not fly; most people do not think they might need care at the end of their lives – and, indeed, in assuming that, they’d be right. It’s a bit of a lottery. The insurers said that people just wouldn’t buy this care.”

People would also opt out of a pensions-style scheme because of this, Forsyth’s committee heard. And such a scheme wouldn’t accrue enough money on time anyway.

Johnson has even less of a plan than Hunt, saying he would look to find “cross-party” consensus on how to fund social care, and spouting obvious principles: that no one should be at risk of losing their home to pay for their care, and everyone in old age should be treated with dignity.

Thanks for that.

The Lords committee concluded that the “national scandal” of social care funding needed £8bn immediately to restore funding to 2009/10 levels, and then universal free personal care over the next five years at a cost of £7bn – all largely funded through general taxation.

Neither of the leadership candidates have come close to pledging such a system. Which is odd, considering they’ve both somehow managed to find lots of money to spend just in time for their leadership hustings.

“I have to say I was a bit nervous about demanding £8bn being spent until I watched the leadership campaign, where they seemed to be able to find money for all kinds of things which are not anything like the priority which needs to be attached to this,” says Forsyth.

“The committee felt rather than a £15bn hit in one year, that was perhaps done best over a period of time, although this was before we discovered the apparent availability of funds which we’re hearing from leadership candidates and from everyone else,” he adds.

“Politics is the language of priorities, and here we are talking about the most vulnerable people in our country, about delivering very basic needs of any civilised society. That should be the first thing on your list when you’re looking at how to spend the proceeds from the tax system.”