The reaction by conservative religious leaders and political commentators to the decision by the ALP on gay marriage has been that this tilt will imperil the party at the next federal election. It may well do. But the reasons supplied are shocking arguments against a call for legitimising gay marriage.
I am not a member of the left-wing intelligentsia and I am not standing for office. But I am a believer in clear reasoning, and what has been written on the subject cries out - if not to heaven, then to the intellect - for a response.
The case for gay marriage has been advanced by various parties and it is not my business to defend their specific arguments or their political ideologies. But surely one might make the following argument for such a move, without regard - for the moment - to the moral prejudices of religious conservatives or the electoral analyses of the pundits.
Sexual orientation is not a matter of ''sin'', but of biochemistry. Gays are a minority that have long been persecuted and vilified in conservative religious societies.
This has too often forced much of their love underground and rendered its practice furtive, undignified and opportunistic. Making marriage possible would be a step in the direction not only of dignifying homoerotic relations, but of making them more moral.
It is surely important here to get a few elementary distinctions clear.
First, there is a sanctimonious claim by conservative Christians and Muslims, and perhaps Jews, that their "holy scriptures" confine marriage to heterosexual relations.
But the idea that any of us should still have our moral reasoning overshadowed by these arcane and morally dubious books is highly challengeable. Especially when it is my understanding that Jesus was on the side of the marginalised and the oppressed. And also that God is love. So if anything, the Christian faith should be advocating for marriage equality.
Surely a liberal, secular society will assess the merits of moral arguments on a more rational basis.
Such a basis might be that there is simply nothing inherently objectionable about homosexual relations and that making it legally and morally possible for homosexual lovers to form a lasting bond would be a constructive step in our society. Let those who insist that they derive their morals from ''holy scripture'' live their moral code without hypocrisy. But there is no sound basis for permitting them to dictate standards of morality in a liberal and tolerant society.
Second, it is argued that the ALP has been self-destructive in espousing a right to gay marriage, since this may cost it heavily in the polls. Cardinal George Pell has been quoted, from faraway Rome, as declaring that ''any Australia-wide party'' that supports gay marriage ''does not want to govern''. Perhaps.
But whether the ALP will suffer at the polls on account of its support for a right to gay marriage has no bearing on whether such support is morally sound or rationally defensible.
One could not, for a century, have hoped to win office in many southern states of the US if one stood for desegregation and civil rights. Did this make these causes morally wrong or intrinsically indefensible? One would not have thought so.
There are many issues, moral and practical, on which it is difficult to win the consent of a majority of our fellow citizens for a wide range of reasons. This may make it politic to avoid espousing them on the hustings.
Yet many of us decry the lack of courage and imagination shown by the political class. They are too driven by opinion polls and concerns in marginal electorates and the single-issue lobbying of special interests, it is again and again lamented.
Well, we have a case study right here. Let it be conceded that the ALP may have miscalculated electorally in this matter. This does not mean that those who support gay marriage are in moral error. It may simply mean that too many of our fellow citizens are narrow-minded, fearful, bigoted and led astray by clerics of one kind or another.
If those who have called for gay marriage are in error, let the case be argued on rational and empirical grounds and not on the grounds that such a moral and legal reform would be inconsistent with Deuteronomy or the Koran.
Those who are not gay, do not have gay friends or do not know gay couples are not well placed to have a sensible opinion on this subject; for it is the freedom of such lovers and couples to live open and dignified lives that is at stake here. Is there anything about actual heterosexual marriages that makes them the gold standard of morality and decency and fidelity? Surely not.
Love and fidelity in marriage are ideals we don't always live up to. Yet if those who see themselves as the moral guardians of our society - an office to which none of us elected them, incidentally - wish to see higher standards of love and fidelity in homosexual relations, might not marriage be a way of signifying precisely that?
And if they recoil from such an appeal, perhaps they need to be reminded that many of us - even if we might still be a minority - have long since repudiated their religious beliefs and claims to moral authority.
What we look for is an enlightened and open society, not a theocratic and reactionary one. We do not see the Bible or the Koran as having any weight in serious matters, moral, historical or scientific. Consequently, we applaud those who raise challenging issues and are prepared to stand up for reforms in the face of conservative reaction and popular prejudice.