Very interesting are the Australian Catholic primate Cardinal Pell's comments on the relation between religion and demographics: effectively he's linking the decline of religion causally to a demographic decline, which in turn is characterised as a disaster. There's two dubious steps here: firstly the causal link, and secondly the normative characterisation. I'm surprised never to have heard this line before, thinking about it: for Christians, it is surely our duty to go forth and multiply? Actually, not really, I suppose. While this is clearly a tenet of Islam, Christianity is much more death-driven: for Christian morality sex is bad. So sex without kids is worse than sex with, since it makes it purposeless sin, but no kids and demographic annihilation is the logical consequence of everyone embracing Christ-like celibacy.
The causal link is basically a joke. Demographic decline is occurring, I would suggest, because of a variety of things including the welfare state (you don't have to have kids to provide in old age), relative economic prosperity (ditto), women's liberation (women have something to do other than have kids – although this freedom has of course been turned against us in neoliberalism, with an injunction to toil replacing the former injunction to breed, driving breeding still lower). It's true that women's liberation is to some extent the outcome of the decline of traditional religion that assigned women to a breeding role, but that doesn't mean it's the result of a decline of religiosity per se – if anything, this is another result of the decline of tradition, which mandated both sexual subservience and religiosity. The welfare state has also partially replaced traditional religion, as indeed has relative economic prosperity. In short, the same social shift encompassing secularisation and low rates of demographic increase – getting back into religion isn't going to help, although getting into Catholicism might since it would mean identifying sex with breeding.
The negative characterisation of demographic decline is something I'm even more surprised not to have seen lately. The only place one typically hear's such talk however, is on the extreme right. It's therefore ipso facto worrying to hear a mainstream figure like Pell talking in a way that obviously connotes notions of racial vitality.