The Tories are losing the shires – this is a gift for Keir Starmer

What Britain wants is a “strong leader prepared to break the rules”. Or at least that’s what it wanted a year ago, when a Hansard Society survey showed that 54% of voters were actively looking for a prime minister willing to play dirty if necessary.

In retrospect, these findings predicted much about the rise of Boris Johnson last summer. His supporters were never so much blind to his flaws – who didn’t know the score by then? – as curiously attracted to them, or at least willing to see their usefulness in the circumstances.

Brexit supporters in particular, exasperated with what they saw as months of Brussels running rings around Britain, argued that you can’t make an omelette without someone cracking eggs. Only now, waist-deep in eggshell, do some of them seem to be realising that the end of rules-based order isn’t as fun as it sounded. And that means something fundamental is shifting.

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Johnson’s personal ratings have plummeted through the Dominic Cummings debacle in a way they didn’t before, even as people’s loved ones were dying, in a sense because this is so personal to him now. Politics is becoming a contest of character, not merely ideology – a choice between government by not-so-lovable rogues who don’t seem to accept that the rules apply to them, and something that for the last few years has been made to look bland, dull and out of touch by comparison. Yet when the alternative seems to be living in a state of rage at what this government is becoming, then playing by the boring old rules suddenly starts to look appealing. Enter, then, Keir Starmer.

The most heartbreaking aspect of this past week has been hearing from people who now feel guilty for doing the right thing, tortured by the thought that in not rushing to see their dying relatives they may have inadvertently let down those they loved. By refusing to admit that Cummings was wrong to exempt himself from lockdown rules, the government is now pouring salt into these wounds.

In an excruciating piece of breakfast radio today, Matt Hancock was repeatedly asked if Cummings had done “the right thing” by driving a carful of coronavirus to Durham. The health secretary could only say, wretchedly, that it was all within the guidelines, which is not only nonsense but the answer to a very different question. The truth is that Cummings may have flouted not just the regulations with his day trip to Barnard Castle – as Durham police have reportedly concluded, or the sense of social solidarity emerging over the last few months, but also a very specific, small-c conservative sense of decency and duty.

That’s why shire Tories are furiously buttonholing their MPs, vicars are revolting, police officers are privately fuming, and the Daily Mail is on the warpath on behalf of middle England. When told to do their moral duty for the good of the country (not least by the Queen, live from Windsor Castle), Mail readers generally do it – and vociferously judge those who don’t. Defending Cummings for failing to do the same is an open gesture of contempt for the values on which the provincial and suburban, golfing and gardening, churchgoing heart of what used to be the Conservative party is founded. And simultaneously it enrages many of the new northern working-class Tory voters on which this government’s majority depends.

The people Labour’s new leader must win back don’t just live behind the so-called red wall, but in southern and Midland marginal towns which used to return Labour MPs in the party’s winning days. Most know nothing much about Starmer yet, except that he has nice hair and once bought his mum a field for her rescued donkeys; but right now that beats defending the indefensible.

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When Starmer says the government’s surcharge on migrant NHS workers for using the service themselves “isn’t right”, or that its repeal is a victory for “common decency”, his language is music to many of these voters’ ears. But it’s also language that Conservative ministers are losing the moral authority to use. Hancock is right that the test-and-trace strategy will work only if complying with it is seen as a “civic duty”, yet the nation’s response is: “Tell that to Dominic Cummings.”

True, there’s a very long way to go, and the Tories retain a poll lead over Labour in the latest polls. Starmer has said nothing substantial yet about the issues that drove a wedge between Labour and some of its traditional vote at the last election, and has barely started on the Herculean task of reconciling Labour’s warring factions. But the party is united over this one dominating issue – and more in tune than Johnson with the public mood. This is a moment that, in four years’ time, we may look back on as decisive.

Some will wonder how voters could swallow everything that has happened over the last few years – austerity, the nonsense on the side of the bus, the reckless threats to leave without a deal, even a mounting coronavirus death toll – only to strain at this relative gnat. But demanding to know why people didn’t see something like this coming when they voted for Johnson is, from a party that clearly failed to offer something more appealing, the wrong question. For the first time, many people are willing at least to look again at a Labour party they rejected only a few months ago, and the last thing they want is a sanctimonious lecture about why they should have done it earlier.

Keir Starmer has been gifted an opportunity by an opponent who doesn’t even seem to realise what he is throwing away. Labour must now show that, not only does it hold the moral high ground, it is fit to govern.

• Gaby Hinsliff is a Guardian columnist