Sylvie Bermann was the French ambassador in London between 2014 and 2017. Her stint here was a notable success. She is a highly intelligent, articulate woman, excellent company, an astute observer of the British scene and a notable anglophile, who generated much goodwill for herself and her country.

She has taken the opportunity of her retirement from the French diplomatic service to write a highly undiplomatic account of her time in London which will lose her a fair amount of that goodwill. Goodbye Britannia is a witty, waspish and angry account of the Brexit referendum and the political crisis which followed it. It is agreeably rude about British politicians, especially the current Prime Minister, whom she describes as a lying mountebank. Her anger tells us something, although more perhaps about the mindset of French officialdom than about Britain.

Bermann writes about Brexit as if it were a personal affront. She regards it as not just a mistake but an outrage. To her, it was a kind of coup d’état against the legitimate regime, a conspiracy by a poisonous minority of Tories which unaccountably succeeded. She finds it difficult to accept that the British might have known what they were doing and voted to leave because they really wanted to leave.

Her explanation of the result boils down to three points. One, the British were manipulated by the lies of the Leave campaign. Two, the British are gripped by post-imperial delusions of grandeur and think that they won the second world war single-handed. Three, they have surrendered to racism and xenophobia.

I hear these superficial clichés all the time when I go to France or Germany. But one expects something better from a professional observer of this country informing the foreign policy of a major European player. Bermann does not even consider the possibility that intelligent Brits might be repelled by the way the EU works, and regard the people who run it as arrogant and remote. She brushes aside the suggestion that a less rigid EU could have accommodated popular concerns which are by no means exclusive to Britain.

Of course there were lies during the referendum campaign, mainly though not only from Leavers. But the British are smart and relatively well-informed. They are avid newspaper readers and have high-quality broadcasting services. They do not believe everything that they are told by politicians. Yes, the £350 million slogan on the side of the bus was a lie, but if you didn’t like paying money to the EU the truth was bad enough. Britain was the largest net contributor to the EU budget after Germany.

Besides, anyone trying to explain the referendum result has to take account of the result of the general election of 2019. If the British were uncertain in 2016 about the economic effects of Brexit and the prospects for a golden deal with the EU, they certainly knew the score three years later, when they voted in the only party opposed to a second referendum with a large majority. The problems of Brexit become clearer every day, but have hardly dented support for it in the opinion polls. Ignorance is not a plausible explanation.

Bermann’s other explanations do not stack up either when you look at the voting patterns. If post-imperial nostalgia contributed to the result, one would have expected to see a big Leave vote in Scotland, which was the real engine of the empire when it existed. The British are not wistful about the empire. They are justifiably proud of their country’s role in the second world war but they do not think that they won it single-handed and are well aware that they have come down in the world since then, like France.

As for racism and xenophobia, it exists but is not a dominant theme of British life and had very little to do with the outcome. The anecdotes which pass for evidence in Bermann’s book are hardly representative. London, with the highest levels of immigration, recorded a large majority for Remain, while Wales, with low levels of immigration voted Leave. In the 2019 election, when the British had come to realise how many basic services depended on migrant labour, immigration hardly featured, but Brexit still won the day. Nigel Farage’s party, which had beaten the drum loudest on immigration in 2016, dropped the issue like a hot brick.

The lesson of the EU referendum campaign, like that of the Scottish referendum campaign of 2014, is that economic arguments are rarely decisive. Regions which derived the greatest economic benefits from EU membership, for example agricultural and pastoral areas such as Wales, or car-producing districts like the north-east, voted Leave. People are more interested in questions of identity and self-determination. There is nothing discreditable or surprising about this. ‘Who are we?’ and ‘How should we be governed?’ are the most fundamental questions that a society can ask about itself.

I write this as an unrepentant Remainer. The European ideal is worth more than the apparatchiks who represent it in Brussels and Luxembourg. Brexit will impoverish us, not perhaps very much, but noticeably. London will no longer be a world city and one of the most vibrant places on Earth. Outside a major political bloc, we will have less influence and less control over our own lives and fortunes. The burdens of membership were great, but the advantages vastly greater.

Many will disagree; but whatever we think about Brexit, it was unquestionably a major event in our history and Europe’s. We do not have to like it. But we do have to understand it better than Sylvie Bermann appears to do.