Here is the crux: “Europe is getting older and will soon be dealing with a serious shortage of working-age people . . . Germany alone could experience a labour shortage of up to 2.4 million workers by 2020, according to the Boston Consulting Group. Our existing social-security systems are not threatened by migration. Quite to the contrary: The contribution of migrants will ensure that the support Europeans receive now will continue into the future.”

Lest anybody missed it, this is an argument for cultural suicide, dressed-up in the language of palliative care.

Even if Europe’s demographic fall-off were as severe as Mr Ambrosi claims, who but a madman would think the answer is to import people from a wholly different culture to make up the next generation? Do Ambrosi and other free-marketeers in America and Europe really foresee no problems at all in this? Perhaps they should explain their theory to the 25-50 per cent of young people in Spain, Portugal, Italy and Greece who do not have a job. Tell them that they have just been leap-frogged by people willing to work harder for less, with the approval of American free-marketeers and assorted libertarians.

Many of us who live in Europe, love Europe as it is. We do not want our politicians, through weakness, cowardice or prevarication, to change our home into an utterly different place. Europeans may be almost endlessly compassionate but not to the point of being suicidal. The public may want many contradictory things, but they will not forgive politicians if — whether by accident or design — they change our continent completely. If they do so then many of us will regret this quietly. Others will regret this less quietly. In either case, if our politicians do not start to lead their publics through this morass then our continent’s crisis may be just beginning.