Screeching tyres, burning rubber, chaos and panic, this U-turn just four days after printing her manifesto is unprecedented – and incomprehensible. Theresa May’s about-face is a shocker, as she announces a cap on what people will pay for their care. She all but abandons one of her few brave and wise policies in a fit of election madness.

Theresa May ditches manifesto plan with 'dementia tax' U-turn Read more

One weekend wobble in the polls and she collapses in a frightened heap. Forget all her mind-deadening “strong and stable” strutting: people will just giggle from now on. In a flash, Tory campaign manager Lynton Crosby’s maddening ear-worm has turned into a weak and wobbly national joke.

Why the fear? She’s nine points ahead in the polls. Nine points! That would still give her a majority of 45-50 seats. The dip in polling, from a 20-point lead before the manifesto launches, is possibly a mid-campaign hiccup that will revert to trend – though her own panicked reaction may mean she bounces back less.

The pretence that this is a “clarification”, not a handbrake turn, is absurd: the manifesto wording and the Conservatives’ own previous briefing said there would be no cap. Wretched Damian Green and Jeremy Hunt were both sent out over the weekend to broadcast categorically that there would be no change: “No, we’re not going to look at it again” (Green); and no cap (Hunt): “We’re being completely explicit.”

Plainly May scares easily, so no doubt all those EU bogeymen that she warns will be watching this election eagle-eyed for any sign of flakiness will duly take note. One puff of wind blows her over. Their teeth may have been gritted, but all the Tory press this morning defended her manifesto “dementia tax”, even the Daily Mail: “Those who can afford it must shoulder some of the cost they receive in old age otherwise the system will collapse under the weight of our ageing population,” its leader column said. Quite right.

What this means is that a new cap on how much anyone need pay for their care will leave working-age people, often non-homeowners, to pick up a hefty bill just to preserve the money of the asset-rich older generation. When Andrew Dilnot recommended a cap of £72,000 on what anyone should pay for their care, the subsidy was going to cost £2bn – to taxpayers who often earn and own less than the wealthy they pay for.

The relevant chapter in May’s manifesto was titled, “A restored contract between the generations”. Well, she has just unrestored it, making the young pay more for the old again. Here’s why her original policy was on the right track: 80% of the retired own their own homes, compared with only 35% of the under-35s. In the course of their lifetime, almost wherever they live, the old have seen the value of their property multiply in a bonanza bubble that has squeezed out the young.

‘In the 20 general election campaigns I’ve followed, I can’t remember a U-turn on this scale' David Butler, psephologist

Perversely, and almost uniquely, the UK doesn’t tax the property people live in, so this unearned windfall escapes capital gains tax. Thanks to former chancellor George Osborne’s super-generosity to the well-off, most of that wealth will never be taxed after death either, except for the richest, with assets over £1m.

Why did Jeremy Corbyn welcome her U-turn? His campaign has been marked by unexpectedly cynical opportunism. However rich, Labour lets the old keep everything, with triple-locked pensions and property untouched by care costs. Abolishing tuition fees for all immediately gifts large sums to mainly middle-class families at huge cost. That money could instead have stopped benefit cuts due to send child poverty soaring. The Resolution Foundation says Labour lets £7bn in cuts continue the freeze; the two-child benefit limit and working tax credits within universal credit remain.

Surprisingly little of Corbyn’s largesse has been directed towards those on low to middle incomes – his £10 minimum wage nowhere near compensates for these benefit losses. This was a moment for Labour to emphasise that the old with assets should be paying for their own care – with a good chance to spell out how that can be done more fairly than May’s plans. While she was right to source the money from the wealth of the old, she came unstuck because she failed to share the risk fairly.

When he was health secretary, Andy Burnham’s 2010 plan was rubbished as a “death tax” by the Tories – but he had a good system to pool the risk, giving everyone the security of knowing what they would pay. Everyone with assets would, at retirement, pay in a fixed sum of £30,000, or pay it after death, spreading the risk between those who drop dead and those who pay for years in a care home. Why didn’t May do that? Or at least graduate whatever fixed sum everyone should pay on retirement according to their wealth? But that smacks of socialism, whereas her cap is a gift to the wealthiest.

Make no mistake, this about-turn is monumental. David Butler, the great psephologist, says: “In the 20 general election campaigns I’ve followed, I can’t remember a U-turn on this scale – or much that could be called a U-turn at all.”

General election 2017: Labour says May's social care U-turn shows 'weak and unstable leadership' – politics live Read more

Andrew Gwynne, Labour’s election co-ordinator, raises the key question: “If this is how they handle their own manifesto, how will they cope with the Brexit negotiations?” That taunt will dog May every step in this election. It will undermine her assault on Corbyn as too weak. Voters may still think she’s the better bet, but every time she struts her stuff they will remember her as U-turn Theresa.

As I write, a pleading message from her drops into my email box, sent out to millions of presumed Tory supporters: “Dear Mary [she calls me by my legal name], it’s a fact that if we lose just six seats, we will lose our majority and Jeremy Corbyn will become prime minister.” She sounds pathetically frit and needy.

To be sure, the Guardian’s ICM poll today puts her five points down – but she’s still 14 points ahead, and she’s terrified. She wants us all to be very afraid too. How stupid does she think people are? The big question is this: how stupid was she to U-turn so easily on a policy that was essentially right and only needed a tweak to make it fairer?

Ahead, the fear is that she will bend and break with every bark from her extreme Brexiteers. This is a bad augury about her character.