Trying to limit the world's population is impossible. It would require an authoritarian world government and that's not going to happen.

Remove tax deductions for more than two kids per couple. Tax the suburbs more highly. Encourage couples to only have two kids just like we encourage people not to litter. Trade less with countries with high birth rates and raise fees on those countries’ environmental impact. All that could be done democratically, no?

Good luck getting the first two passed into law, at least in the US. "Encourage couples..." will get no traction. We still have a ton of littering, and all the religious groups in the US (the Quiver Full movement etc) will love that. Cutting trade based on a country's birth rate and adding tariffs based on EI etc will be extremely problematic.

Sure anything can be done "democratically." But politics is the art of the possible...

Punitive taxation and restricting trade with Africa wouldn't be a good look...

https://en.wikipedia.org/wiki/List_of_sovereign_states_and_d...

(Not to say it's only Africa by any means, but you do have to go quite a ways down the list before you hit a non-African country).

Sure, but would it be worth it? I suspect yes; the alternative is continued population growth leaving very little natural world on the entire planet and all of us eating an industrially farmed diet.

You would said 500 million people 200 years ago.

Malthusians in 200 years will say 50 billion.

Is this helpful? I mean, we’ve already passed the point of too much natural habitat lost and too much industrial ag needed, so I think a number less then our current population is reasonable.