I should also note, that I am for mandatory euthanasia, say at about the age of 68 and I believe in maximum of 1 child per couple to stem over-population. I also love sterilization of the stupid, dumb and obese, so let's start setting the standards and culling the "herd" before it's too late!!!
It is more complex than that to be certain, but the future will be rife with hard choices. As it stands today how much food does the US grow for other countries due to ... overpopulation? I'm not just talking the big 2 of China/India, I'm talking smaller nations, but because food doesn't fucking grow there, we've taking it upon ourselves to do the humane thing and not let them starve to death (as much), now expand that outward and how much food can we produce for the rest of the world keeping in mind that takes away from the US not just food but other resources like water, California is a big issue now with this, even though a lot of it is cash crop exports the idea is the same. Will you want to change your lifestyle of the wide range of food you can eat just because people make more babies than food in other countries? Then extrapolate even further where the US does put a hardline "fuck that shit" stance and we slow down food exports, then you have imports ... of people moving to where the food is. I mean you think people complaining about immigration now is bad, it's going to get much MUCH worse.I can kinda get your point but I think its way more complex than that.
An aside on feeding Africa (just to enlighten those that don't work in U.S. trade policy and might be wondering where some of your tax dollars go each year).
This is a multi-pronged issue to be sure.
1) The production of food here in the USA, especially crops (not so much fruit / vegetables though) are supported by U.S. legislation (Google "Farm Bill" if you are really interested),
2) The later exports of those same crops to foreign countries, including Africa, are further supported by entities & mechanisms like loan programs from the US Ag. Dept. and the Ex-Im bank (which supports the sale of US goods to foreign countries).
3) Money from "aid / relief organizations" like the State Dept.'s US AID often have government procurement requirements tied to the aid money, i.e. You want to take our money you also have to buy only from US companies with that aid money.
An example - it is cheaper (with all of the subsidies and incentives) for an African country to buy imported food / rice / corn from the USA than it is for an African farmer to try to grow it locally (paying out of pocket) and sell it themselves.
In this regard, the subsidized US growers (using your tax money via things like counter-cyclical payments, conservation payments, the commodity credit corporation) are putting the local African growers out of business and ... keeping them out of business / always on the teat.
TLR - the US government uses your tax money to pay US farmers to grow crops cheaply, then gives more money in aid subsidies & loans to foreign trading partners (incl. Africa) to buy that very same merch, keeping these countries from developing the infrastructure to grow / produce crops for themselves and stuck on the foreign / US aid.