[throwawaylinux]

Carbon footprint per capita is a poor metric because it incentivizes nations to increase population and suppress quality of life improvements.

If you want to assign blame sure an American might be 10 time more responsible than a Pakistani, a Chinese may be twice as culpable is a French. That doesn't really solve anything though. The problem isn't the amount of CO2 in the air divided by the number of living humans.

Emissions intensity of production IMO is a better one because it promotes efficient industry without exerting the wrong incentives on population or quality of life.

[AlgerianSam]

The problem is total amount of emitted CO2. A large extent of it being emitted by a rather reduced fraction of the total population (rich countries).

Seems rational to exerce change of this reduced fraction. Indian or Pakistani are respecting their share in terms of emissions in order for climate increase to stay under 2 degrees. We are not, so we need to change that.

[throwawaylinux]

When you say "we", policy that can affect carbon emissions and even population trends to some degree are usually made on a country level. So it makes sense for highly emitting countries to reduce their emissions, not for them to be able to purchase "share" by encouraging population growth.