Cast your minds back to the spring of 2020. The weather was glorious, bright blue skies enticing people out of doors for their daily socially-distanced pandemic walk. In the scenic market town of Barnard Castle in County Durham, some who ventured out on April 12 were startled by the sight of Dominic Cummings and his wife on a path near the river.

Shouldn’t the Prime Minister’s chief adviser have been in London, at the helm of the government’s Covid response operation? And what was he doing, 300 miles from base, when everybody else was abiding by the stay-at-home injunction imposed by Boris Johnson?

Amidst the dread and gloom of the early months of the pandemic, fury about Cummings’s escape from the metropolis provided a welcome distraction. We all remember his excuses. He claimed that by leaving the capital to join his wife and child at her parents’ home in Durham, when he was suffering from Covid, he was acting within the guidelines. The subsequent 25-mile trip to Barnard Castle on his wife’s birthday was legitimate, he said, as he was testing his eyesight before making the long return journey south.

The ensuing kerfuffle was little more than a sideshow as the virus tightened its grip, yet it offered an insight into the way Johnson’s chief aide viewed himself: in short, above the rules he helped set.

In retrospect, as became clear in the first two episodes of the gripping three-part BBC Two docuseries Laura Kuenssberg: State of Chaos, Cummings’ slip-up would prove fateful.

By November 2020 he had been forced to resign. He left No. 10 with the surly demeanour of a teenager asked to empty the dishwasher, and for this we should be profoundly grateful. If it had not been for the Barnard Castle debacle, Cummings might to this day be in the heart of government, undermining the establishment like a latterday Guy Fawkes. Contemplating what condition the UK would be in if he were still at the controls is enough to raise a cold sweat. 

Kuenssberg, formerly the BBC’s political editor, puts her impressive contacts book to good use as she attempts to show “how close our political system [came] to falling apart”. It was instructive that even such a seasoned Westminster observer sounded genuinely disturbed at the scenes she had witnessed or the back-room revelations confided to her.

Interviews with a slew of (mostly) Tory politicians and, more unusually, with senior civil servants and advisers, confirmed what we already knew or suspected. In the early days of Johnson’s government, there were effectively two prime ministers: one democratically elected, the other – Cummings, on whom Johnson leaned far too heavily – the real power in the land.

Perhaps the most shocking admission by Cummings, taken from an earlier interview, was that although Boris had returned to Downing Street with a whopping majority in 2019, “we talked about replacing Johnson as PM a month after the election win”.

Whoever “we” alluded to, they had no illusions that he was a credible long-term prime minister. It appears that being faithful to the electorate and the fundamentals of democracy were irrelevant to this cabal’s  ambitions. It’s fair to say that a septic tank is more wholesome than the state of Westminster in those Borgia-like days.  

The simmering cauldron of Conservative disarray and revolt under Theresa May’s leadership was unedifying in every respect, from the PM’s crippling  indecisiveness to hardline Euro-sceptics baying for a no-deal. Hearing rabid Brexiteer Steve Baker boasting of working all hours to topple May was sickening. In previous centuries such behaviour would have brought him to the gallows. At least in those days rebels knew they were risking their necks; today’s revolters have no need of backbone, just a mobile phone.

Listening to testimony from inside parliament, it became chillingly plain that Cummings presided over something approaching a very British coup: engineering the exit of top civil servants, and creating a culture in which, as a whistleblower from the Foreign Office recalled, there was the expectation that staff would “cover up for mistruths if necessary”.

That concerns were raised with Buckingham Palace about the treatment of the civil service shows how badly the cracks in the system threatened its survival. Whether in times of crisis or calm Westminster depends on the dispassionate, experienced counsel of its civil servants to function well. That its bureaucratic foundations were rocked is an indication of how  perilously near to the edge our political firmament came.

Anyone interested in how our democracy works should watch this series. I await the third episode, which will cover Liz Truss’s calamitous 44 days in office, with a mix of trepidation and fascination. The alarming truth already revealed by witnesses to Westminster’s turmoil is how tremendously fragile the state is. This is especially so when those in power are buffeted and bullied by forces within their own party that care nothing for stability or the fate of the country, and everything for their own cause.  

Since Cameron stepped down, the governance of Britain has been swayed by ideologues, as inflexible and judgemental in their views as religious fundamentalists. What was so shocking to observe, with the distance of hindsight, is how vulnerable parliament is to such manipulation. Bad enough the idea of foreign spies working from within to disable the system; infinitely worse when it is elected representatives who are tunnelling beneath the floorboards; and frankly terrifying when unelected anti-establishment heidbangers can exert so much authority.  

Under the Johnson government, principles that were once taken for granted as the unshakeable bedrock of power have turned into Raac, crumbling to dust and threatening to bring the entire edifice down. When such decay sets in, it takes a very long time to rebuild trust and confidence.

At present, we are a long way from the restoration of faith in how Westminster works. Previously we lived by the assurance that, no matter which party was in power, its focus was the good of the country and the bolstering of democracy. That no longer pertains. Now, everything feels conditional, contingent and cynical.

Who’s to say that the ship won’t fall into the wrong hands again? We’ve already seen what happens when it comes close to hitting the rocks. Considering the turbulent times we’re living through, just how long do you think our luck will hold out?   

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