This is the only way because today space exploration is limited to where you can go. Overpopulation is a serious problem. This is a problem that will begin to haunt humanity today and will continue into the distant future if nothing is done about it. If each couple had only one child, the population would be controlled. And, if possible, only people who can really support the child should have them. People in slums should not reproduce if the child will grow up poor and malnourished. Even though humans have the right to give birth it doesn't mean they should. Just as it is the right for children to grow up to become better, so as not to have to live in these conditions. This is why population control must exist. Not for the people of the past, but for the future of humanity