DOMINIC Cummings aimed to destroy his former boss last week. But he blew himself up instead with his intemperate j’accuse. Mr Johnson should really reward his former chief adviser – ennoble him as Baron Dom of Barnard Castle. He’s done him a great service.

Bizarrely, in his seven hours of evidence, Cummings achieved the impossible: he all but exonerated Johnson from personal responsibility by revealing that the entire civil service and the scientific community were caught unawares by coronavirus and were gripped by herd immunity groupthink. Cummings was part of it too. He admitted he didn’t advise the PM to seriously consider lockdown until it was already too late.

Cummings also saved the bacon of the hapless Health Secretary, Matt Hancock, by accusing him of repeatedly lying. Boris Johnson was forced to back his Cabinet minister, thus saving him from the chop in the forthcoming cabinet reshuffle.

Cummings may also have done the PM a favour by helping expose the hypocrisy of Nicola Sturgeon. Her claims to have handled the pandemic better are now sounding distinctly hollow. She can expect a flurry of compensation claims following the admission that the Scottish Government failed to protect elderly patients in care homes

It was quite a performance. No wonder Boris Johnson practically purred at Prime Minister’s Questions on the day The Dom lobbed his self-destructive hand grenades. Not so much Independence Day as the Great Escape.

I felt almost sorry for the dark lord as he exposed his personality disorders in what almost became an Oprah-style confessional. Cummings’s most revealing moment came right at the start when he nearly broke down while delivering an apology to those who died needlessly. He is clearly a troubled man.But he squandered it all by a display of arrogance, ignorance, pettiness, vanity, malevolence. Of unreliability and disloyalty – not just to Boris Johnson, who stood by him over Barnard Castle, but to the civil servants, scientists, ministers whose trust he betrayed to no good purpose.

It is fine to be a whistleblower – provided you know how to blow it.

In more competent hands Cummings’s evidence, especially about Johnson’s dithering over the second lockdown last autumn, might have done real damage. But his accusations either missed their target or rebounded. Not least when Cummings declared that everyone at a senior level in government was “crackers” – including himself.

The main charge against Boris Johnson has always been that the PM was reckless, uncaring and throughout the pandemic, putting the interests of the economy above human lives. That he wilfully ignored scientific advice and thought we should just “take it on the chin”. Cummings made clear that, on the contrary, Johnson’s failings were a reflection of a dysfunctional civil service run by amateurs and by a scientific community which was fighting the wrong pandemic. It was chaos, from top to bottom. Whitehall said it had a plan but didn’t. The Government’s scientific advisers thought they were dealing with flu. No-one – Cummings included – advised the PM to take any serious action, such as quarantine and closing the borders, until mid-March. Even then the borders were not closed for fear it would look “racist”. Large gatherings like Cheltenham were allowed to continue.

In hindsight, Johnson’s scientific advisers should have learned from the prompt action taken by some Asian countries like South Korea that had experienced the Sars and Mers outbreaks. But the point was: they didn’t. Cummings underlined that international agencies – like the World Health Organisation and the US Centres for Disease Control – were also slow off the mark.

Even after the pandemic was recognised as such in March 2020, the consensus on the Scientific Advisory Group on Emergencies (SAGE) and in Whitehall was that, in the absence of a vaccine, the disease had to be allowed to “work its way through the population” until herd immunity was achieved. The aim, as Cummings explained it, was to seek immunity by the autumn, to avoid a second wave in winter.

This was all wrong, of course. Coronavirus was much more contagious and lethal than flu. But Cummings portrayed this as a collective failure that could not solely be laid at the door of the PM however “unfit” he thought he was was for office. He even quoted the Cabinet Secretary at the time, Mark Sedwill, advocating a Covid version of “chickenpox parties” to help spread immunity.

Cummings should have pleaded the Fifth because he then incriminated himself. In January and February 2020, he did nothing. He didn’t even attend Cobra meetings, didn’t advise lockdown, didn’t even discuss what lockdown meant seriously until that infamous “Independence Day” meeting on March 13 in Downing Street. That was when his whiteboard told him disaster was imminent and that the PM needed a “Plan B”. Unfortunately, the then-Deputy Cabinet Secretary Helen McNamara burst in saying “there’s no plan – we’re absolutely f****d”.

The next day, March 14, Cummings still did not call on the PM to impose a full Wuhan-style lockdown. He was just “too scared that I might be wrong”. Anyway, he said, SAGE “had not modelled any kind of lockdown” because it was still labouring under the logic of herd immunity.

Yet if there was no Plan B, who might be thought to be at least partly responsible for that, if not the most influential adviser in government: Dominic Cummings? He had even blogged about the dangers of coronavirus pandemics before entering government.

I ended up agreeing with Boris Johnson: chaos would indeed be better than putting this monomaniac in charge of anything. Cummings even said that, given his choice, he would have put a “dictator” in charge of the pandemic.

It doesn’t take a genius now to forecast what the official inquiry is going to say whenever it reports. There was a systemic failure to plan going back several administrations. The scientific advisers, and Whitehall, failed to appreciate just how deadly Covid-19 was. The Prime Minister’s advisers, from Cummings down, failed to alert him until it was too late. Lessons will be learned etc.

Prime ministers are not scientists, they rely on advice from civil servants, special advisers and medical experts. Cummings even distanced Johnson from the most serious scandal of all: the deaths of some 30,000 care home residents. Cummings pinned that on Matt Hancock who, he said, lied about testing elderly patients before they were decanted from acute wards. Hancock says he didn’t promise anything of the sort.

Nicola Sturgeon may regret jumping on the Cummings bandwagon and accusing Johnson of being responsible for “loss of life”. Some 3,026 old people were decanted from Scottish hospitals during the first wave, many without a test. Compensation lawyers are already sharpening their writs.

As this column has pointed out before, the Scottish Government made all the same mistakes – it did not lock down early enough, halted community testing, neglected care homes. The Scottish excess death rate is one of the worst in Europe. Ms Sturgeon accused Johnson of failing to impose a circuit-breaker lockdown in the autumn. But she didn’t impose a full lockdown then either.

Perhaps she now needs a Cummings figure to help spread the blame.

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