“In the three years since leaving the EU, we’ve made huge strides in harnessing the freedoms unlocked by Brexit,” Sunak said in a statement marking the anniversary. “Whether leading Europe’s fastest vaccine rollout, striking trade deals with over 70 countries or taking back control of our borders, we’ve forged a path as an independent nation with confidence.”

His predecessor, Boris Johnson, also cited the early authorisation and rapid deployment of a coronavirus vaccine as proof of Brexit’s value – never mind that health experts said Britain would have had the authority to approve a vaccine before its neighbours, even if it had been part of the European Union.

“Let’s shrug off all this negativity and gloom-mongering that I hear about Brexit,” Johnson said in a video posted on Twitter on Tuesday afternoon. “Let’s remember the opportunities that lie ahead, and the vaccine rollout proves it.”

There is little evidence that Sunak and Johnson are convincing many people. Public opinion has turned sharply against Brexit: Fifty-six per cent of those surveyed thought leaving the European Union was a mistake, according to a poll in November by the firm YouGov, while only 32 per cent thought it was a good idea.

And the sense of disillusion is nationwide. In all but three of Britain’s 632 parliamentary constituencies, more people now agree than disagree with the statement, “Britain was wrong to leave the EU”, according to a new poll.

But at the same time, few people express a desire to open a debate over whether to rejoin the European Union. The prospects of doing that on terms that would be remotely acceptable to either side are, for the moment, far-fetched. The Labour leader, Keir Starmer, prefers to frame his party’s message as “Making Brexit Work”. The party lost an election in 2019 to the Tories, who had the slogan “Get Brexit Done”.

Britain’s problems are exacerbated by the fact that the one leader who proposed radical remedies, Liz Truss, triggered such a backlash in the financial markets that she was forced out of office in 45 days. To restore the country’s reputation with investors, Sunak has scrapped her tax cuts and adopted a fiscally austere program of higher taxes and spending cuts that the IMF says will curb growth.

“Although we no longer have lunatics running the asylum, we have essentially a lame-duck government that doesn’t have any semblance of a plan to restore economic growth,” said Jonathan Portes, a professor of economics at King’s College London.

The trouble is that the bitter squabbling over Brexit has made obvious responses politically perilous for the prime minister. Even the IMF’s projection for Britain’s growth ignited a storm of commentary on social media about whether it would help the cause of “Remainers” or reopen the Brexit debate.

The fund’s assessment was not completely gloomy despite its prediction of contraction in 2023. Britain, it estimated, grew faster than Germany or France last year. After inflation cools and the burden of higher taxes eases, it said, Britain should return to modest growth in 2024.

Portes said there were policies Sunak could pursue, from liberalising planning laws to overhauling immigration rules to ease the labour shortage, that would stimulate growth. “If you put all those together,” he said, “there is a reasonable, feasible strategy that could make the next 10 years better than the last.”

But he added, “Any coherent strategy involves repairing the economic relationship with Europe, and that will depend on the political dynamic.”

This article originally appeared in The New York Times.

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