The obscure herpes virus which science just found can make a woman infertile could be spread in places where more people usually leads to more war (wink).
Maybe we are too late for the Trump family but for future generations I can think of a lot of places where this could prove beneficial. How about members of ISIS, and let's not forget the Hindus with all the class structure - Royal families will just go out and spread wild oats as they say. It has been the case with the likes of Charles Martel and Hitler whose bastard lineage is a clue.
All in all we can provide for almost unli9mited people IF we had a plan to be productive but we do NOT. So let us hope the infertility virus spreads like wildfire.