Root Problem of Potential Societal Collapses

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The root problem in all but one of Diamond's factors leading to collapse is overpopulation relative to the practicable (as opposed to the ideal theoretical) carrying capacity of the environment. The one factor not related to overpopulation is the harmful effect of accidentally or intentionally introducing nonnative species to a region.

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12 environmental problems facing mankind today

Here are all 12 environmental problems that humans now face on earth at once:

1. Deforestation and habitat destruction
2. Soil problems (erosion, salinization, and soil fertility losses)
3. Water management problems
4. Overhunting
5. Overfishing
6. Effects of introduced species on native species
7. Overpopulation
8. Increased per-capita impact of people

Further, he says four new factors may contribute to the weakening and collapse of present and future societies:

1. Anthropogenic climate change
2. Buildup of toxins in the environment
3. Energy shortages
4. Full human utilization of the Earth’s photosynthetic capacity

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Collapse: How Societies Choose to Fail or Succeed"

So, as we witness Arab Spring for example, we in the western world might see this as a potential triumph of democracy in the middle east. Whereas what actually may be happening there is overpopulation problems in relation to natural resources of those areas. For example, there may be too many young people being born for the environment to actually support. So when young people there get into their 20s and can't get a good enough job to get married or have a family they get upset. This upsetedness transfers into anger and rage and this tends to overthrow governments. However, when there aren't the natural resources to cover everyone this only causes governmental collapses (unless) they are an oil state which can then afford to pay for higher prices for food, water, shelter etc. for their people which can be imported in from other areas. However, if those other areas are impacted by similar problems the people in areas where the food is being imported from might starve. So, this can become a vicious cycle for many areas on earth.