Britain is failing to cope with the COVID-19 epidemic as well as other countries in Europe and East Asia have. Out of 62,000 excess deaths in the UK, says former chief medical officer Sir David King, “40,000 excess deaths could have been avoided if government had acted responsibly”.

The failure is devastating: on a single day this week, 359 people died from coronavirus in the UK – more than the number of deaths in all 27 EU countries over the same 24 hours. The UK is starting to exit lockdown while the epidemic has not been brought under control, despite all the economic self-destruction.

Two main reasons explain why the crisis in Britain turned into a calamity. Firstly, the political consequences of Brexit turn out to be more lethal and swift than any potential economic damage. It is now clear that the worst outcome of the turmoil over leaving the EU has been to land Britain with a leadership of spectacular incompetence during one of the worst crises in British history.

Boris Johnson emerges, when he does emerge these days, as the sort of shallow self-promoting buffoon that his critics, including many who know him well, have always said that he was. As his government’s failures multiply, his default position is evasion and denial: on the very same day that Britain (population 66 million) outpaced the whole of the EU (population 446 million) in fatalities, Johnson told the House of Commons that he was “very proud of what we have achieved”.

Much of the time it does not matter much who is nominally running a country with an effective civil service, but this is not one of those times. Judgements crucial to the lives and livelihoods of millions must be made, but at this critical moment, Britain is finding that it is run by a Gilbert-and-Sullivan type administration. The analogy is all too appropriate: Johnson, with his fake-patrician bombast and shady dealings, strongly resembles the Duke of Plaza Toro in The Gondoliers who “led his regiment from behind/he found it less exciting”. The sinister character and dubious doings of Dominic Cummings strongly recall those of the Grand Inquisitor in the same opera.

Almost everybody outside the government believes that at no point during the epidemic has the government been ahead of the game. It has always lagged behind and frequently headed in the wrong direction. The list of errors is long: underestimating the threat posed by the virus; failure to prepare for it through accelerated procurement; late and inadequate testing and tracing; sending untested COVID-19 carriers into care homes; failing to introduce face masks early on; chaotic preparation for a return to normal life and resumed economic activity. In combination, these mistakes may keep Britain in semi-lockdown for the foreseeable future.

Once Britain had a reputation for having one of the world’s most astute political classes operating through one of its most effective administrative machines. No longer: the pandemic marks the turning point. Johnson and mediocre ministers have throughout conveyed a frightening sense not of malignancy but of amateurs at work, lightweights baffled by what is happening and unable to learn from experience.

Britain is paying a high price for the whole bizarre Brexit project, not so much because of the undoubted economic damage it will do to the country, but because of the inadequacy of the leaders whom it elevated into power. Anybody who seriously believed that Britain’s troubles stemmed primarily from membership of the EU was either a crackpot, a careerist or simply misinformed. Though claiming to see a golden future for global Britain, the Brexiters were unashamed “Little Englanders”, their isolationism neatly expressed in the apocryphal weather forecast, “Fog in channel, continent isolated”.

From the beginning of the crisis this attitude has hobbled cooperation with other countries or even learning from their experience. The Brexiters’ instinct to stand proudly alone in defiance of reality presumably explains the decision to impose a 14-day quarantine period on travellers arriving in Britain, where coronavirus is still rife, though they may be coming from countries where it has been largely suppressed. This reminds me of travelling to Russia and Iraq in the 1990s, at a time when the health systems in both countries had collapsed and diseases were spreading unchecked, and finding that all arrivals had to have an Aids test.

The second cause of Britain’s all too “world beating” fatality rate, to adopt Johnson’s famous boast, is the degree to which the operational capacity of the UK government has withered in recent decades. Ministers make self-confident claims about the delivery of testing, tracing, PPE equipment, an app to prevent the spread of the illness and other initiatives, but nothing happens or delivery is halting and unreliable.

Britain is discovering the hard way how far its administrative machine has been weakened by cuts and outsourcing. Central government has monopolised authority and resources and starved local authorities of both, though they should be on the cutting edge of “test and trace”. An editorial in the British Medical Journal of which the lead author is a professor of European public health, Martin McKee, succinctly sums up what has happened: “A hollowed out civil service has long turned to outsourcing companies, despite their repeated failures. Companies with little relevant experience have struggled to organise viral testing or contact tracing. The task of coordinating activities with existing organisations, such as NHS laboratories or local public health departments, is too complex for their business model.”

Testing and tracing are central to the government’s bid to contain the epidemic. This is scarcely surprising since Dr John Snow, one of the founders of modern epidemiology, first mapped cholera victims in Soho in London in 1854 in order to identify the origins of a cholera outbreak (it was a water pump producing polluted water). More sophisticated “trace and track” campaigns have since been used to suppress or contain epidemics. Such detective work needs well trained and experienced interviewers to get total strangers to disclose their movements and contacts. German health officials today credit a well-organised “test and trace” system for their success in bringing the epidemic under control in Germany by 17 April, just six weeks after the first death there from the virus.

In Britain, the recruitment of 25,000 contact tracers has been partly outsourced, 10,000 of them being recruited by Serco and its subcontractors. Directors of public health only learned on the morning of the announcement that the test and trace effort was being launched four days early. It will now only be fully operational by September or October according to its chief operating officer.

The main explanation of the government is that it, along with all the governments in the world, was surprised by the speed and ferocity of the virus. This excuse might have had some validity in February or even March, but not now. Coronavirus has now killed almost twice as many people as died in the Blitz – 32,000 – and most of them should still be alive.