So what do they really mean? Nowhere in yesterday's "ground-breaking declaration on immigration" by some of the country's "leading Parliamentarians" is there any mention of race or religion. They describe themselves as "cross party" and their manifesto – baldly entitled "70 million is too many" – talks about the "significant impact" of a growing population on "our public services, our quality of life and on the nature of our society".
They're a bit too pleased with themselves, bragging that their declaration "marks an important moment in the debate about immigration", but they're at pains not to single out any ethnic or religious group.
Given that the text has been constructed in studiedly neutral language, it may have been a mistake to allow Lord Carey to speak for the group in a series of broadcast interviews. No, said the former Archbishop of Canterbury on yesterday morning's Today programme, the declaration was not an attempt to put a limit on immigration from non-Christian populations. But he went on to insist that immigrants need to "understand" the UK's culture, including Parliamentary democracy, which is "built upon Christian heritage".
This is the same Lord Carey who wrote a tendentious article for the News of the World less than two weeks ago, complaining that Christianity is being "systematically marginalised" in this country. "Make no mistake," he thundered, "our laws, literature and national character are hewn out of our national religion – Christianity."
Carey made the breathtaking claim that Christians might have to engage in "civil disobedience" in defence of their faith, and completely ignored the long counter-tradition of secular radicals who have made their mark on British history. Indeed I would argue that many of our most treasured freedoms had to be wrested from the iron grip of the Church, and I'm delighted to hear a former archbishop admit that "the vital connection between the Christian faith and the British people is increasingly disregarded".
If that's the case, I can't help thinking that believers are over-represented among Carey's fellow-signatories. It's true that the declaration is cross party – 10 Tories to Labour's six – but they're all white and at least half are practising Christians.
As well as the former Archbishop, the complete list of 20 includes a member of the General Synod (Frank Field MP), a couple of prominent Roman Catholics (Peter Kilfoyle MP and Michael Ancram MP), the son of a bishop (Robert Key MP) and several practising Anglicans.
Among the peers on the list is the cross-bencher Baroness Cox, who hosted an event at the House of Commons last year highlighting "the persecution of Christians in the United Kingdom". This is something of a theme for Cox, who once helped launch a book by a Nigerian missionary entitled Great Britain Has Fallen!
I suspect there is a great deal of nostalgia among this little group, a yearning for a country which never really existed outside public schools, the higher echelons of the Church of England and the early novels of Agatha Christie (which, on reflection, expressed similar fears about a rapidly changing world).
That suspicion is reinforced by the fact that what the declaration calls for – a manifesto commitment by both main parties to reduce net immigration to fewer than 40,000 a year – is totally unenforceable while the UK remains in the European Union. Oh, but I forgot: Baroness Cox is a member of BOO, the hard-line Eurosceptic organisation Better Off Out, and it's chaired by another signatory, the Tory peer Lord Vinson.
It wouldn't be fair to suggest that the signatories are racist but their vision of a UK hiding behind its borders, clutching its Christian values to its bosom like a torn dress, certainly isn't one I share. I'm not even sure that the debate they're calling for has much to do with immigration, since it feels more like a coded protest about what they believe the country has already become.
Take one practical point: anyone who is genuinely worried about population growth should call for wider use of birth control and smaller families, but these are policies actively opposed by the Catholic church. They should also argue for better education for girls and women; the more education women get, the fewer children they have, lifting them out of the poverty associated with large families and allowing them to take a full role in civil society. Establishing gender equality among disadvantaged groups, whether they're white working-class or from ethnic minorities, is a more effective way of implementing universal human rights than demanding impractical limits on immigration.
It's a depressing fact that the people who think of themselves as the great and the good in this country – "distinguished", according to their own press release – are often remarkably small-minded. Frankly, when we're faced with pompous declarations of this sort, one is already too many.