The decline of western civilisation makes perfect sense, given how humans within societies function and interact. Almost all children survive childhood now, so there is not the need to "over-produce" children. Modern societies are oriented around college educated professions and occupations--and the "slots" for those professions and occupations can be easily saturated in many communities. This saturation of high level jobs also suggests that there is not a need for more children.
But actually, there are several reasons why western parents need to produce more children. Besides the significant dearth of skilled craftsmen, skilled maintenance persons, skilled construction workers, skilled technicians and technologists, and particular areas of engineering and information science with a shortage of trained people, there are other needs for more intelligent and educated humans. The needs are dictated by the future, which will present many openings for intelligent and well-educated humans that have not yet been imagined.
You cannot expect most modern westerners to understand how successful societies are organised, and they do not. That is one reason why universities emphasize obsolete and worthless areas of study, while neglecting others that are vital for the future.
It is no surprise that most modern westerners have little understanding of how a society--or civilisation--is structured and maintained. Societies evolved over time, and with specialisation of labour people only understand their own small piece of societal reality. The public acquires its understanding of society by way of school teachers, university professors, journalists, popular media, and their peers.
The schools, universities, news media, and entertainment media are all dominated by leftists. Leftists are particularly ignorant about how society works, due the top-down elitist nature of how leftist ideas are propagated. The elitists on the left have specialised into a niche that has very little competence-testing, and very little interaction with most of the real world.
In emergency situations, most leftists are of little use because they are so dependent upon governmental services that they have no concept of self-help. New Orleans and Louisiana, after a recent hurricane, were under the control of leftist governments, and were virtually helpless until the federal government was able to take over total control of the situation. The next large emergencies may not be so localized or so mild. Contrast that incompetence in Louisiana, with the extreme competence demonstrated in Florida during recent natural disasters.
It is not necessary to understand modern leftism other than to know that it is controlled and propagated from inbred cloisters of ideologues who have lost touch with the reality beneath the reality of civilisation. These ideological mutants are incapable of comprehending a threat to civilisation, nor would they have the least idea how to respond to a threat once it was so blatant and horrific that they could no longer deny its existence.
That is why you see leftists paradoxically rushing both to the banner of "climate change catastrophe" and to the banner of "peak oil catastrophe"--while they vehemently deny any threat to the civilisation that has given them their freedom to mutate for over two hundred years. Leftists appear to secretly cherish the hope that islamist fanatics will bring the downfall of mainstream governments, and pave the way for leftists to finally preside over the Internationale. For such a prize, these ideologues will allow the cracking of a few eggs, to make the omelette.
But most people are not leftist ideologues, despite all educational attempts to make them so. Most people in western societies possess ample intelligence and curiosity to learn basic skills of living, and the basic underlying workings of a society and a civilisation.
Even in the undeveloped third world regions, people have the innate sense to deal with the environment, as long as they are not expected to maintain a technological infrastructure. It is the relative sophistication and wealth of the west that has motivated the islamist drive for conquest of the west. All of that technology and wealth makes Islam and Allah look bad--inferior. That can not be allowed to happen, at least if the mullahs, imams, and ayatollahs have anything to say about it. They will spend the last drop of muslim blood in proving the superiority of the desert moon god, if they must.