Yet when the Adoption and Children (Scotland) Bill was approved on Thursday, by a convincing majority, there was no moral shift at all. Unmarried and single-sex couples can now apply to be joint adoptive parents; before, only married couples or single people, including gays, could adopt.

The legislation, designed to make more people eligible as parents and thus address the massive drop in the number of adopters, brings Scotland into line with England and Wales. Similar laws were passed there four years ago without the subsequent collapse of civilisation.

But still the controversy rages, bringing together some unusual bedfellows. Predictably, Cardinal Keith O’Brien, Scotland’s Roman Catholic leader, has been vociferous, describing the move as “gravely immoral” and a “distorted social experiment aimed at redefining marriage, subverting the family and threatening the good of society”.

He has had staunch support from Roseanna Cunningham of the SNP, herself a Catholic, who disagreed so vehemently with the adoption bill, and with most of her colleagues, that she tabled a series of amendments (which were defeated) to block it. Adding their weight were Alasdair Morrison, the Labour MSP for the Western Isles, four other MSPs, and the Scottish Christian People’s Alliance, which calls itself a political party.

Whenever society moves forward by displaying greater tolerance towards minorities, there is always a handful of zealots who can be relied upon to defend their prejudices to the end. We should not be too surprised by the usual suspects; the Catholic church would not be expected to condone the extension of further rights to homosexuals.

And in the strictly conservative Western Isles, whose councillors were alone in Scotland in banning civil partnerships for gays, the Free Church’s position is clear: homosexuals shame their community. “We are years behind the rest of the country,” said one gay islander.

As with the Catholic church, the issue is not so much about adoption but about a fundamental, faith-based discomfort with homosexuality. But beyond this, there remains a palpable unease in the general public over gay adoption. O’Brien might claim to speak for the 16% of Scots who are Roman Catholic but, as always, his views resonate outside his parish.

Although public attitudes have changed — with only one-third of people now opposed to a change in the law on same-sex adoption — and although the Church of Scotland has officially backed the new legislation, and even senior Tories are on-side, the perception that it is “unnatural” persists.

Gay politicians, and even cabinet ministers, no longer merit attention, and gay clergymen and soldiers are increasingly acceptable. Gay rights campaigners have been so successful that there is not much left to campaign for. The exception is in the domain of the family. As soon as children are mentioned in the same sentence as homosexuals, especially homosexual men, the old hang-ups resurface and the old clichés — traditional families and normal role models — are trotted out.

As Cunningham insisted, people who go along with the principle of gay adoption are “in the business of saying that nature got it wrong”. How shallow this is. In a perfect world all children would be raised by their own mother and father in a loving and stable environment. Nobody would ever get divorced, or die prematurely, and no child would grow up not knowing who their father was.

In the real world, however, such “normality” cannot be guaranteed. Children from all backgrounds live with cohabiting or stepparents and with half- or step-siblings. There are now 174,000 single-parent families in Scotland, a rise of 24% since 1997. Divorce rates have stabilised, not because fewer relationships fail but because fewer people get married. Although evidence suggests that children born in traditional nuclear families are more likely to achieve good exam results, thousands of children thrive nonetheless in unconventional households.

And on the flip-side, bad things can happen in “intact” families, as has been borne out by a number of tragedies this year involving real fathers and their dependent offspring.

Just about any family, though, provides better odds for a child than being placed in care. Children who have been in care make up about 0.5% of the population in Britain but they account for a quarter of the adult prison population. Of the 6,000 who will leave care this year, 4,500 will have no qualifications, according to the think tank the Centre for Policy Studies. Within two years, 3,000 will be unemployed, and 2,100 will be single mothers or pregnant. Just 60 will make it to university.

In Scotland, the number of children in care is at record levels. Meanwhile, adoption applications have fallen from 1,000 a year to 400 over the past 20 years. It is now more common for older children, often neglected or abused by their biological parents, to be put up for adoption than babies.

By opening up the system to more potential parents who will, of course, be rigorously assessed, more children will have the chance to make something of their lives.

This is already taken for granted in many countries, without their societies spiralling into immorality, as O’Brien would have it. In South Africa, for example, the practice has been established for more than four years, offering refuge to hundreds of children orphaned by Aids.

The new law here does not pander to political correctness, unless you count concern with the welfare of children as politically correct, and those who opposed it on religious grounds should try to rise above their misgivings.

And those in the gay lobby, who say the attacks on their suitability as parents have hurt their feelings, should remember — as we all should — that this is not about them. It is about children.

jenny.hjul@sunday-times.co.uk

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