Lord Mackay may well be forced to extend the 12-month cooling-off period in his Bill to 18 months. But the moral zealots are unlikely to rest until they have used every parliamentary device they can to undermine the central reform principle of "no-fault" divorce.
Many of Lord Mackay's critics, such as Baroness Young in the Lords and the former education secretary John Patten MP in the House of Commons, seem hell-bent on making mischief. For them, the removal of blame from the business of divorce is tantamount to removing responsibility for relationship breakdown.
These fundamentalists see the permissive Sixties as the root cause of our contemporary problems, bringing not only the pill and sexual freedom, but also divorce and abortion law reform as well. Sometimes one wonders if they and their supporters actually accept the idea of divorce at all. They certainly seem overly obsessed with symbolic politics - the sanctity of marriage must be upheld in all cases - even if that means endangering unmarried victims of domestic violence, which was the implication of their successful battle to kill off the Domestic Violence and Families Bill in the last Parliamentary session.
And this week they are in ebullient mood once again, their supporters such as William Oddie in the Daily Mail celebrating the fact that the Tory party, "at the last gasp, is suddenly rediscovering its identity as the party of the family and marriage". In this climate it is a bold Conservative minister who would persist in championing what Oddie calls "a piece of legislation for a throw-away age - if it doesn't work, don't fix it, dump it."
It's all a bit ironic. When Lord Mackay's Bill was first proposed, many read it as an attempt to make divorce more difficult, because it introduced the idea of a 12-month cooling off period. Those in favour of quickie divorces said this was simply 12 months too long.
Indeed, if the Bill becomes law, Princess Diana and Prince Charles may well find themselves having to wait for a cooling-off year rather than obtaining an automatic divorce after their two-year separation. (Perhaps this explains the Queen's recent pressure for a rapid decision from the unhappy couple).
In fact, the Bill has turned out to be a sophisticated attempt to strike a balance between the need to make the process of divorce less gladiatorial and at the same time to ensure that people really do understand the significance of their decision to part. One of the benefits of removing fault and building in a cooling-off period is that it creates a climate in which people may arrive at calmer and more collected decisions about whether the relationship has irretrievably broken down.
This is important because research consistently shows that many people use the divorce process as a cry for help or as a way of testing their relationships. In one academic study in the late Eighties, 51 per cent of divorced men and 29 per cent of divorced women would have preferred to stay married; and in 10 per cent of cases, both parties wished that they had remained married. So it seems that many people don't know whether their relationship is at an end and may be using the legal system as a way of finding out.
Soap operas have been quick to dissect these themes, with tales such as that of Patricia and Max Farnham in Brookside, a couple with marital problems who divorced in haste and decided to remarry the day the divorce was made final.
By actively encouraging couples to attend mediation and seek counselling during their cooling-off period, Lord Mackay's Bill compels couples to think again. It also recognises that fault and blame need to be removed from the process so that partners can come to the negotiating table not with the belligerent attitude of war-time foes but one more conducive to conflict-resolution.
It is this shift away from our fault-based system to one that rejects the whole notion of pinpointing blame that may, in the long run, be the most important. Until now we have been content to caricature the process of relationship breakdown as one of victim and perpetrator, institutionalising a divisive blame culture.
But as most of us know, real life is rarely that simple: more often than not both parties bear some responsibility for relationships gone wrong. So by removing the concept of blame in the divorce process, the Bill creates a space for both sides to face up to their own responsibilities. The break- up itself can become less acrimonious, aided by a built-in delay that encourages couples to solve their disagreements, especially over issues such as access to children, in an amicable manner.
Recent research conducted by Relate's Centre for Family Studies at Newcastle University found that mediation proved effective at resolving disagreements between couples, 80 per cent of married couples reaching some form of agreement amicably, often in the best interests of the child.
For the familial fundamentalists such arguments fall on deaf ears. In their eyes, blame is vital to the divorce process: in their twisted logic it upholds the sanctity of marriage itself. Thus they are content to condemn those living in the real world to pain: for fault-based divorce almost always guarantees misery and conflict, and sours bad relationships even more, with obvious detrimental effects on the children of the warring parents.
This is why the Bill is an important shift in public policy, a recognition of the fact that the greatest problems arising from unstable relationships are those involving children, and that the State is bound to take a role in protecting their interests. The combination of no-fault and cooling off is the most child-friendly piece of divorce legislation that has ever been put before Parliament. But the fundamentalists seem blind to the needs of children and are left asserting an old version of state responsibility, by wanting the law to prescribe the boundaries of adult relationships and tell people how to live their lives.
How the Prime Minister handles this will be of vital importance because such issues inevitably have a wider resonance. The 1992 Republican Presidential Convention proved to be a turning point for George Bush in his bid for re-election to the US presidency. His party was shown to have been taken over by the moralistic, Christian fundamentalist Right, whose zealotry was anathema to most Americans. John Major, burnt once already by "Back to Basics", should take heed and beware the hectoring of the moralists in his own party.