It is understandable that opposition to contraception has become, in the popular mind, the main defining feature of Roman Catholicism, or at least its senior hierarchy.
And it is notable that the RC Church hierarchy has utterly failed to convince its flock to follow this teaching - since the most RC dominated countries of Europe are among those with the lowest fertility (Ireland, Spain, Italy).
To have failed does not, of course, mean that the RC hierarchy were wrong. Indeed, they may have had little choice in the matter since sex-without-conception was the main (ahem) thrust of the culture war when Leftism clashed with institutional religion from the mid-1960s onwards.
But the deep problem of the RC emphasis on no-contraception is that it strikes so many people as senseless - specifically, I mean in breach of common sense.
This is probably because the RC opposition to contraception is not common sense, nor is it core Christian teaching; rather it is a distal, logico-philosophical consequence of some core Christian teachings.
In particular, the opposition is expressed in Thomistic terms of the intrinsic function of sex, as inferred from the complementarity of sexes, that they fit together - plus some scriptural back-up, and therefore the permissible occasions and types of sex.
All this is way too fine-spun and drawn-out for people to comprehend - especially modern people with their short attention span and impatience.
The obvious core basis of RC opposition to contraception is pro-natalism - that marriage should aim to be fertile, that having children is good, that larger families are better (so long as they are self-supporting, at any rate).
Yet, the attempt to yoke contraception to pro-natalism fails - there is no necessary nor observable reason why contraception cannot be linked with pro-natalism - as among the Mormons.
(Mormons are not exactly pro-, but in practice not-against-contraception, and nearly all Mormons use contraception. Yet Mormons, unlike Roman Catholics, have been successful in their pro-natalism, with significantly above-replacement family sizes (greater than 2.1 children per family) and much larger families than RCs especially among the wealthiest and most educated.)
And, indeed, there is something terrifying in the modern world about pro-natalism without contraception - fertility can get terrifyingly out of control.
For tribal hunter-gatherers, living on a hunter gatherer diet, the maximium number of babies a woman can have is probably around six - because menarche is late and pregnancies are spaced-out by lactation acting as a natural contraceptive (and if this fails the newborn baby will nearly always die, be abandoned or killed - since there is not enough milk for two and the older child is usually privileged).
(Of these six, an average of two survive to reproduce, in the steady population state.)
On a more modern, agriculture based diet, with high levels of fat and protein, menarche is earlier and lactation is no longer a natural contraceptive and women can have a lot more pregnancies going to term - ten births is not unusual, and even more is not uncommon.
Such fertility rates either leads to massive death rates among children (e.g. about eight deaths per family), or else requires rapid economic growth or massive support from outside the family.
This was the norm for pre-industrial revolution societies: the average peasant had near-zero surviving children - regardless of fertility.
Of course, there is an alternative - celibate marriage. That is possible among the most devout of certain populations with high intelligence and conscientiousness; but is not possible for most of the people in the world most of the time. Celibacy must be enforced on them, or it won't happen. And the sanctions must be extreme, encompassing the death of surplus children - otherwise the celibate devout will merely be amplifying the numbers of incontinent apostates, generation upon generation...
So, this is the reality of the Roman Catholic combination of pro-natalism and anti-contraception under modern conditions.
I am not saying that this is an unacceptable reality, because it was the state of affairs for some thousands of years; but I have never seen it honestly set out.
Now, of course, people don't exactly and explicitly realize that this is the reality of Roman Catholic teaching on contraception - but they do sense intuitively, by common sense, that combining pro-natalism with anti-contraception under modern conditions leads to unacceptable outcomes: either ten kids leading to impoverishment plus/ minus life on welfare - or else a life of reluctant monkish celibacy.
So, which is more important? Pro-natalism or anti-contraception?
We can see that modern Roman Catholics have voted with their feet, or rather loins, to abandon both.
My first point is pragmatic (merely) and is that pro-natalism is vastly more important than anti-contraception; and given the perceived conflict between the two, pro-natalism should have been what the RC hierarchy pushed hard, while saying little or nothing about contraception.
My second point is theological/ religious - which is that the Church should take care to be definite about core teaching, and indefinite about derived teachings - since the derived teachings are vulnerable both to logical errors and - more importantly - to the errors of logic.
In my opinion, it is an intrinsic flaw of Western Christendom (including the Roman Catholic Church, and also the Protestant denominations) that they feel compelled to give a philosophical opinion, indeed lay down the law, on all conceivable matters - to create a coherent, internally-non-contradictory and fully-comprehensive intellectual structure.
Yet Christianity is a religion of mystery and incomprehension - right at its core. Philosophy and Law are an optional extra - and should not be allowed to usurp the core mystery. When the specific and the explicit usurp the mystery we have the tail wagging the dog.
Christianity cannot win battles of law and logic on worldly matters like the precise details of sexual practice - rather the 'answers' to these must emerge (for each person) from the primary recognition of the core mystery.
The core mystery, in this instance, being to do with the mystical unity of Mankind (at the level of souls, a web of salvation) and the special (sacramental) importance of marriage and birth - this was one of the distinctive teachings that set Christianity apart from paganism.
In a wider sense, the modern Christian Church needs desperately to recover its mystical focus, even at the cost of setting aside its focus on specific moral conflicts.
People break the Christian Laws because they cannot understand, cannot feel, the reason for these precise Laws - and without this feeling the Laws seem merely arbitrary.
And sometimes the Laws are - if not arbitrary - then not tightly consequential. Some Christian Laws are the result of a chain of logical reasoning, and only as secure as the process of logic - which is to say not necessarily secure. Natural Law and Revelation trump logic.
I do not, of course, mean that Christianity should go-along with modernity and accept its 'reforms' and constraints - but these should be reacted to simply by getting on with things, and refusing to budge on core issues - without argument and 'rational' discourse, preferably; just a stubborn holding to tradition and ancient wisdom in the face of insatiable desire for change and progress fueled by shallow nihilism.
In other words, we ought to live by the built-in assumption that under modern conditions any proposed change is almost certain to be wrong and harmful and must therefore be resisted for at least a few generations - after which it may cautiously be tried-out.
In sum, my discomfort and indeed irritation with the Roman Catholic focus on contraception and other issues of precise sexual conduct is part of a conviction that the Christian Church must at this point in history eschew worldliness as much as possible, to develop and emphasize instead the Heavenly, mystical and prayerful, salvific core.
Christ followed the spirit of The Law, even as he broke the letter of specific laws.
Justice is not the outcome of applying specific explicit laws; but the use of specific and explicit laws to attain Justice.
The same applies to specific ethical rules, such as those pertaining to sex within marriage.
Legalistic hyper-correctness is not a solution to laxity; it is indeed merely to substitute one form of sin for another.
The only solution to laxity is sanctity.