Population growth historically received a lot of attention, but at this point there's enough queued up people waiting to join the West's way of life it looks to me like that ship has sailed.
China promptly overtook the US in co2 emissions as they arrived in the past few decades [0], by a wide margin. What does the world look like when India starts competing with China for that position? They certainly have the headcount for it, at least they're mostly vegetarian right? For how much longer...
[0] https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...