i'm thinking that we're going to run out of nonrenewable resources in 80 years at this point, and then we'll have 10 billion clueless people all demanding resources for themselves, where we can slow the use of nonrenewable resources by a ton if we didn't have so many freaking people
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and don't give me the "I'm one year older than you so I'm smarter" excuse
First of all, that's an excuse for a god damned gibbon, so forget that.
Second, the decline of population in a single country will not do anything to assist in the diminishing of our use of non-renewable resources. We've been on the track of complete exhaustion of the resources that we do have since the Industrial Revolution; the difference is that it wasn't until the late 1960s that we started to realize, "Hey, we kind of forgeted up."
Yes, Japan is in the top ten for most populous countries in the world. If the entire state of Japan were to disappear at this very moment, the world's population would barely fluctuate. In fact, we would still maintain our population of ~7,163,683,810.
The point I'm attempting to make is that any change in population won't cease the overuse of natural resources. To say we should
celebrate a lack of growth in a country is loving cornball. At this point, we haven't reached oversaturation, let alone overpopulation of the Earth. The US Food and Agriculture Organization expects a total of 9 million people by 2050, but even then the Earth will comfortably be able to support such a population.
I don't think you realize this, but Japan isn't overpopulated in the slightest. It's developing countries that are overpopulated, they don't have enough resources to go around.
Combined with the fact that birth control is not advocated in developing countries, leading to a high birthrate in contrast to a much higher mortality rate.