Ministers have struggled to wear a mask. Do they think it makes them look weak?

Whatever he has done to Wagamama’s previously enviable reputation, Rishi Sunak has demonstrated that, even in one of those countries where the leadership is also a recognised disease vector, some hygiene failures can still shock.

We might be resigned to a clammy-looking Boris Johnson transmitting virus between hand, home and lectern; to a health secretary who, also ignoring his own advice, sneaks up behind colleagues in his deadly pink tie; or to a chief adviser who seems positively inspired by the plague-spreading achievements of medieval body lice; but still – spraying saliva over meals?

The most striking thing about last week’s waitering stunt was surely that Sunak didn’t wear a mask, nor disposable gloves, to serve food. You wondered, given this departure from restrictions now accepted everywhere from buses to hairdressers, if Sunak even washed his hands for as long as it takes to say “Bolsonaro” before he picked up plates of chicken katsu curry – a dish that is admittedly overdue for retirement.

No doubt many of us have spent too much time studying diagrams of how far a laugh/cough/sneeze sends infected matter leaping over supermarket aisles and government benches, but if so, why hasn’t Sunak? Ignorance or idiocy? If he hasn’t missed the compelling evidence on the effectiveness of masks in reducing Covid-19 transmission – including a study on the eve of his Wagamama trip – perhaps he fears, like various prominent maniacs, that he might come across as effeminate, cowardly, leftwing. But even proudly brutal Republicans are now submitting.

If only to recommend to nervous customers his meal-deal route to economic recovery, there was no rational reason for Sunak to lose an opportunity to normalise mask wearing in confined public spaces.

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Asked about his performance, Sunak said: “I’m keen to try and get our message across to as many people as possible.” And to give him credit, one thing could not be clearer. He has been wildly overpraised.

There was a further lesson from the missing face mask: the government’s understanding of disease control remains as lethally inferior to the public’s as it was when workplaces were emptying but Johnson’s message remained “shake hands and go to a rugby match”.

In fact, the sight of Sunak bantering over his petri dishes reminded me to check on some face masks I ordered at the end of January, some days before Johnson scorned virus-related “panic”, depicting his own government as “ready to take off its Clark Kent spectacles and leap into the phone booth and emerge with its cloak flowing”, and so, abjectly, forth.

I’d resorted reluctantly to the world’s most detested supplier, more far-sighted mask buyers having already exhausted the stocks of tax-paying businesses. Clearly, long before the science was clear, people didn’t need a politician or senior medical officer to tell them that face coverings might represent a harmless potential obstacle to the flying droplets of crap, or whatever you called it, that were spreading a devastating respiratory disease with no cure.

But this was before sustained official advice discouraging the non-specialist use of masks. Some early and prospective adopters will therefore have abandoned an effective health measure whose popularity in other parts of the world we were repeatedly urged to dismiss as medically irrelevant cultural differences. “It is entirely wired into some cultures that masks are worn quite frequently in open spaces,” explained the admired Professor Jonathan Van-Tam.

Professor Whitty: “Our advice is clear: that wearing a mask if you don’t have an infection reduces the risk almost not at all.” Matt Hancock: “A front door is better than any face mask.” Dr Jenny Harries: “You can actually trap the virus in the mask and start breathing it in.”

Then there were, Harries warned, “behavioural issues” – a great concern in the team that held that mere respect for life would not ensure lockdown compliance from a public believed, for some reason, to be as suicidally libertarian, or staggeringly selfish, as Johnson and Dominic Cummings. “What tends to happen,” Harries explained, in a prediction that would shortly be contradicted by a surge in fabric mask buying, “is people will have one mask. They won’t wear it all the time, they will take it off when they get home, they will put it down on a surface they haven’t cleaned.” Stupid people.

An official resistance to normalisation, which could almost at one stage have been understood as legitimate anxiety about PPE supplies, or about enforcement, is now, following mounting evidence of both mask efficacy and behavioural compliance (including in historically non-mask-wearing countries), ever more inexplicable. Survival aside, the government seems indifferent, even, to the profits, the more absurd end of this surging market having become, inevitably, a Veblen sector, featuring Samantha Cameron’s “silk cobalt leopard pansy print”, £25 (sold out).

“Cloth face coverings are effective in reducing source virus transmission,” says another study. A majority of the population is amenable. Countries such as Germany, also with no history of mask wearing, mandated face coverings months ago. Earlier, when it exposed the public to lethal risks, the government could attempt, by the repetition of “unprecedented” and its ever diminishing claim to be “guided by the science”, to defend its exceptionalism. What is the argument now? Masks save lives but, outside public transport, the Westminster government won’t impose them. In refusing to do so it adds to the risks of transmission, and to the difficulties of workers and customers attempting to keep themselves safe. Mask avoiders, however, are indulged.

As Tom Hanks said last week of mask wearing: “I don’t get it, I simply do not get it, it is literally the least you can do.” Although Hanks probably missed a critical Johnson column. Perhaps the science could tell us how many lives were lost to official mask resistance before the prime minister finally risked being derisively compared with a bank robber.

•Catherine Bennett is an Observer columnist