When someone wants the impossible, in French we say that they want “the butter, the money from the butter, and the dairymaid’s smile”. In more vulgar usage we say they want something rather more from the dairymaid than a smile. This is precisely what we can take away from Theresa May’s speech on the “hard Brexit” she wants. It is “hard” only for the other 27 states but “soft” for Britain – because May wants to keep all the benefits of EU membership and concede nothing in return. That is not really a surprise since she had already announced it in October during the Conservative party conference. She even considers that any other kind of agreement would be unacceptable, because it would amount to “punishing” the British.

May is threatening to turn Britain into a tax haven by way of retaliation, if, by some misfortune, the Europeans refuse to bend to the demands of Her Glorious Majesty’s subjects.

We might think we are dreaming, but no: it is either arrogance or recklessness (or, more likely, a mixture of the two).

Let’s sum up: on the one hand, of course, May would like a clear, “clean break” with the union, which means no longer sitting in its institutions, contributing to the budget or respecting EU law. On the other hand, she does not want the status of some kind of “partial or associate” member, which would imply having to meet EU’s requirements in all kinds of areas.

Thus far, we get it: the UK will be treated like any other third country – Zimbabwe, for instance. That’s clear and “clean”. But after that it gets complicated, at least for a continental mind that lacks the subtleties of reflection of a product of Oxbridge. Because May considers it possible for British companies to retain the greatest possible access to the single market, in particular to negotiate sectoral customs agreements with the union. And that’s where things get interesting. Because customs duty or no, importing goods into a market presupposes compliance with local norms and standards: to be clear, if the British want to export their cars (which are in fact German or Japanese cars) to the continent, they need to respect European laws. That means submitting (I know, what an awful word) to those laws. So in reality, the clear, “clean break” could only concern one part of UK industry – the part that manufactures for the local market.

Above all, May says nothing about services. How, for instance, can banks retain guaranteed access to the continent, a necessity as soon as the City is no longer a financial centre for the euro? What does Theresa May envisage offering in exchange? Because with all due respect to UK national sentiment, the reality is brutal: we are talking about a mid-ranking power of 65 million people, most of whose industry is owned by foreign capital, negotiating with one of the world’s principal trading, economic and monetary powers – a power that comes with a market of 450 million people. Which countries does Britain export to, and where does a good part of its foreign investment come from? Where is the power? Who has the most to lose in all this? Threatening that Britain will become a tax haven if it doesn’t get what it wants amounts to childishness: such a solution might be possible for a micro-state without its own industry, but not for a country like Britain.

Can anyone imagine the other EU nations allowing their companies and capital to relocate to the UK without responding in some way? Would Britain’s new American ally, which has threatened its own companies if they offshore their profits, allow May to transform her country into some kind of aircraft carrier for tax optimisation?

Even worse for May, she should not count on the 27 governments dividing on this issue. They have a huge amount to lose politically if they approve an agreement favourable to the Brexiteers, which would only reinforce their own national europhobes. Seen in this light, a soft exit is not only technically meaningless, it is politically absurd. On the other hand, any agreement must be unanimously ratified by the 27. If not, in March 2019, Britain will simply be out. To divide the remaining member states is to ensure there will be no deal.

In short, you can twist Brexit any way you like, but I see only one loser. And it is not on the continent.