Demographics is destiny. You can go Yahoogle birth rates by nation and see who is growing and who is dying.
Another useful way of looking a global demographics is by the median age of each nation.
The Global Median Age is 30.1 as of 2016 estimates. The darker parts of the map are older: Europe, North America, Japan... and the younger nations are in green and yellow.
The median age of the Palestinian Territories is 19, and almost all African nations are lower than that.
The median age of Germany--a very old country--is 47, with the rest of Europe all in their 40's. The US stands at 38, thanks to all the children arriving here, since our native-born birth rate is not much better than Olde Europe.
This explains the epochal global migration we are living through. Nature abhors a vacuum.
What do we do about it?