Per capita isn't the useful metric in this regard for the reason Palau illustrates. The climate cares about volume.

Per capita emissions is a way to assign relative sin by those who feel guilty about living large.

Bill Gates today, "This is a chance to refocus on the metric that should count even more than emissions and temperature change: improving lives. Our chief goal should be to prevent suffering, particularly for those in the toughest conditions who live in the world’s poorest countries. The biggest problems are poverty and disease, just as they always have been. Understanding this will let us focus our limited resources on interventions that will have the greatest impact for the most vulnerable people.”