It is a matter of time before the earth goes on, nuclear war, and self-destruction. Human science, logic and analytical intelligence far exceed morality, relationship coordination, social management intelligence, and finally, when mutual hatred is uncoordinated, it will be self-destroyed by war.
The current civilization of this earth is very likely to be the second time, or third time civilization, which has been eliminated by the former human beings.
The only fair and effective way to save the world is to realistically assign birth rates based on racial pros and cons and IQ, for example:
Central Asian Islam 1%;
Chinese and Southeast Asians 1%;
American Chinese 2%;
West Asia, 5% of North Asians;
Eastern European whites 10%;
Western European Nordic White 100%.
In this way, the population of the earth is optimized, the world will be out of imbalance, and the war which mostly come from human evolution unbalance，the world will get better.
Of course, I expect universities would establish an ethnographic research program to train population-optimized experts and scholars.
This final reasonable ratio can be determined by population-preferred scientists through genetic testing and quality studies.