“I’m only wearing a mask because everyone else is. When they stop, I’ll stop,” one customer announced to anyone listening at my local supermarket last week. The cashier agreed vigorously. A few days later, a middle-aged woman screamed at a maskless man on my train: “Don’t you understand you’re endangering me and everyone else on this carriage?”

Few topics divide England right now like whether to mask or not. For a year, face coverings have been compulsory on public transport and in indoor spaces. In pubs and restaurants, patrons have been ordered to don them while moving around.

Only a small minority has rejected this new orthodoxy outright. Yet there has always been something reluctant about the British adoption of masks. A recent visitor from the US told me they were shocked at how few people in London wear them compared to New York.

The debate is particularly obvious in the Palace of Westminster. Like most workplaces, masks are currently required for shuffling around its corridors. Staff manning the libraries and coffee shops are fully masked while the libertarian Conservative MPs march around with their faces uncovered, bristling whenever officials remind them of the very guidelines that the government put into law.

This same bloody-mindedness lies behind Boris Johnson’s decision to drop the legal requirement for masks, along with almost all other Covid measures, from July 19. Even though cases are running at more than 30,000 a day and hospital admissions have jumped by 48 per cent in the past week, Johnson has framed it as a move away from “government by diktat”.

Much of his decision was forced by parliamentary arithmetic. A growing number of Tories argue that the need for masks has passed thanks to the vaccination programme. One backbencher, Miriam Cates, recently claimed (incorrectly) that there is no scientific consensus on masks. She won’t be wearing one because “freedom is very important”.

A senior government minister confesses that Johnson’s hand was forced. “Colleagues have reached the end of their tether with restrictions. We couldn’t have got [continued restrictions] through on Tory votes and there’s no way we could have passed with Labour. It would have been the end of Boris, so he indulged his libertarian side,” they say.

Whitehall is now aflutter with speculation that, since public opinion is set against him, Johnson will have to U-turn. According to the pollsters YouGov, two-thirds of Britons plan to continue wearing masks after the legal requirement ends. Another survey from Ipsos Mori suggests that 40 per cent would like to keep them permanently in shops and on public transport.

But England’s psyche is more complex than polls suggest. The success of the vaccination programme, with two-thirds of the UK having received both doses, has lessened the need for masks everywhere. But the risk of dropping the legal requirement is that the nation indulges its own libertarian side and bins them all together.

Making masks optional risks spreading coronavirus more quickly. Graham Medley, a member of the government’s scientific advisory committee, argues they only work if “everyone does it”. Even if 70 per cent continue to wear them, most of their effectiveness disappears. “I understand the government’s reluctance to actually mandate it. On other hand if it’s not mandated, it probably won’t do any good,” he says.

The impending easing of England’s coronavirus restrictions is the biggest Covid gamble Johnson has taken so far, possibly a career-defining one. If the central assumption behind the plans proves correct, the prime minister will have delivered a skin-of-his-teeth success of reaching hybrid herd immunity through mixing injections and infections.

But if it goes badly wrong and England returns to restrictions or even lockdown, his reputation will take a severe battering. Militant Tory MPs will rebel, leaving Johnson reliant on Labour to put the measures into practice. The public will be unforgiving too: the Tories’ vaccine bounce in opinion polls may disappear. Faced with all that, keeping masks in some public settings seems a small price to pay.