With a limited land mass and a dense population it is the natural factors which will ultimately determine the future.
The US was able to prosper during the previous 200 years because it continued to expand into the wilderness. This is now reaching its limit and the consequences are becoming more obvious.
Africa is still undeveloped and is giving away (rather than using) much of its resources. So, if the management issues could ever be solved, it could improve its standard of living. China and India will both become disasters since they already exceed the capacity of their natural environments. Raiding weaker states for inputs can only go on for so long and will require increasing militarism. This will be countered by the present developed states which are also in competition for the same resources.
The only solution is to realistically address overpopulation. This is not on anyone's agenda, so we can expect uncontrolled disasters, some man-made and some natural. Policies not Politics ---- Daily Landscape