Boris Johnson is standing by his man. It risks undermining his entire coronavirus strategy

One wing of our party is going collectively bonkers by comparing a four-year-old’s toilet break to the invasion of Suez, the UK crashing out of the ERM,” wrote Danny Kruger. He warned fellow Tory MPs that calling for Dominic Cummings to quit amounts to a declaration of no confidence in Boris Johnson.

When you think Team Boris can’t raise the stakes any higher, they do. But we shouldn’t be too surprised by Kruger’s intervention. He was previously Johnson’s political secretary and is a friend of the Cummings family.

But his reference to a “wing” of the Tory party is intriguing. Since the Cummings saga began, five days of damaging front pages ago, some of his cheerleaders have hinted it is a plot whipped up by his enemies, including left-wing Remainers seeking revenge on the architect of the 2016 Vote Leave campaign, who now want the Brexit transitional period extended.

This is bonkers. I don’t think Steve Baker, Peter Bone, Tim Loughton and Philip Davies, who are among the 40 Tory MPs calling for Cummings to go, qualify for membership of that club.

The truth, conversely, is that the Vote Leave camp is trying to save Cummings’s skin. When the cabinet met on Monday, calls for him to stay were led by the prominent Brexiteers Jacob Rees-Mogg, the Commons leader, and Suella Braverman, the attorney general, a remarkable intervention by the government’s senior law officer given that Durham Police are still investigating Cummings’s actions. Nor is it any surprise the Downing Street machine is trying to keep Cummings since it includes several of his former Vote Leave colleagues; his demise might signal theirs.

The only “wing” of the Tory party that wants Cummings to depart is the sensible one. Today’s opinion polls show it speaks for voters. Johnson said people would make up their own minds about his closest adviser and it is clear that they have done. According to YouGov, the Tories’ lead over Labour has dropped from 15 to six percentage points in the past week, the biggest fall in a decade. Cummings’s extraordinary press conference on Sunday only made matters worse; seven in ten people think he broke the lockdown rules, including 63 per cent of Leave voters. No Remainer plot among the public either.

Johnson has gambled that standing by his man will not undermine his entire coronavirus strategy by encouraging the public to ignore the rules. But some ministers and government scientific advisers fear it will. Indeed, YouGov found 70 per cent of people believe the Cummings row will make it harder to get future lockdown messaging across to the public, while only 18 per cent think it will make no difference.

This is happening at a critical moment. The government will soon announce details of its “test and trace” operation in England (the “track” bit seems to have been dropped because the public doesn’t like its Big Brother feel). This has been speeded up in the hope of reassuring parents and teachers ahead of the planned reopening of schools in England on Monday. (The much-trumpeted contact tracing app is unlikely to be ready; it appears to have gone from being the cake to a possible cherry on the top.)

Crucially, some people who come into contact with those who get coronavirus will be “instructed” to self-isolate for 14 days – even if they have no symptoms. A big ask, for example, for people ordered not to see family or friends, exercise outside their home or go out to work.

The ask, and the task of ensuring compliance, has been made even bigger by the Cummings affair.

The government will also need the public’s support for localised lockdowns when there are flare-ups in workplaces, schools, hospitals and housing estates, and for the 14-day quarantine for those returning from abroad after 8 June. Who could blame people for using their “instincts”, “a degree of personal judgment”, “common sense” or “exceptional circumstances” affecting their children – all excuses ministers have cited when tying themselves in knots to defend Cummings? This, more than the impact on Johnson’s or the Tories’ ratings, is what makes the affair so dangerous.

Today’s polls will not surprise No 10, which pores over its almost daily surveys of 2,000 voters. Team Boris hopes the public will tire of the media coverage, and the storm will eventually blow itself out without permanent damage. Optimists among them will recall that Tony Blair’s ratings slumped during the 2000 fuel protests, yet he won another landslide the following year.

But what if Kruger is wrong and this is an “ERM moment”, when people make up their minds once and for all about a leader, party and government, as they did after John Major’s exit from the European exchange rate mechanism in 1992? Ominously, Major suffered a humiliating election defeat four and a half years later. That is also when Johnson’s mandate will expire.