Eastern Europeans call it the great 'Re-migration'. Economies are booming. Wages are soaring. Poles, Balts, and Magyars are returning home.

So are Spaniards, drawn back to their own country after their Lost Decade. Let us not underestimate the gravity of the economic crime committed against the youth of Southern Europe by those who constructed monetary union and then ran it into the ground.

Yet Europe has turned the page on that sorry saga, and this has enormous ramifications for Britain. The EU migrant shock that hit the country in two great waves over the period from 2004 to 2016 is abating. We can now see that it was one-off effect, an historic aberration.

Theresa May's cardinal sin is to misjudge these economic forces, fixing doggedly on the one issue of immigration in Brexit strategy as if nothing had changed.

To the extent that there is a 'trade-off' between access to the EU economy and power to restrict EU labour flows, the calculus should at least reflect reality on the ground.

It is abject statecraft to risk grave damage to UK industry and the City – or to undermine Britain's "soft power" as an open liberal nation – in order to tackle an issue that is self-correcting anyway.