So now we know for certain what many have long suspected. Uncontrolled migration is costly to the people who already live here.

New research from the Conservative Party shows that each worker in this country will – by 2031 – be worse off by roughly £2,500 a year thanks to large-scale inward migration.

No doubt there are some who benefit from various forms of cheap labour. The metropolitan wealthy classes – who include many in the media and politics – have seldom found domestic servants as cheap as they are now. But, in general, immigration means downward pressure on all our wages.

A strange coalition of crackpot multi-culturalists, open borders ideologues, Marxists and virtue-signalling liberals see no problems in this. But everyone else does. It is time that it was addressed.

The extraordinary scenes in the Spanish enclave of Ceuta have rightly alarmed all who have seen them. Ceuta, within sight of the Rock of Gibraltar, is one of the very few places where the poor world and the rich world are divided by nothing more than a fence.

And last week that fence gave way, amid disturbing violence and chaos. Many of those who forced their way in were dismayed to find no gold-paved streets when they arrived, just a not-especially prosperous Spanish seaside city.

They have now left and the immediate crisis is over. But for how long? What if all the barriers – between prosperous, law-governed countries and the grim regions which have neither wealth nor law – disappeared? They are under obvious strain.

Across the Mediterranean and the English Channel, the boats and dinghies stream, making a mockery of border controls and migration rules.

There are plenty of arguments about the best response. Some say the new wave of migration has been caused by Western-sponsored wars of choice and we should stop them. Others blame the weakness of leaders such as Germany's former Chancellor Angela Merkel, who simply flung her country's border wide open, with disastrous results.

Others suspect that Left-wing governments actively want more migrants, hoping that the new arrivals will end up voting for them. Others, some of them on the Right, claim unconvincingly that migration boosts Western economies.

Not for most people it doesn't, as we now see. And all this time nobody has found a civilised, workable way of stopping the boats.

This has been going on for years now. Several EU nations, interestingly, are looking at versions of the Rwanda scheme proposed by the last Tory government, under which unwelcome migrants are sent to a third country.

One of Sir Keir Starmer's many foolish errors was to petulantly abolish this programme just as it was beginning to show signs of having an effect. Labour, which flung wide our borders 25 years ago, simply is not interested in serious migration controls. Andy Burnham shows no sign of changing that.

But the Tories are now free, if they wish, to renounce past mistakes and to develop a serious and intelligent policy, which serves the people of this country and their needs, and which makes it plain to the world that Britain will not make the same foolish error that Mrs Merkel made.