[belorn]

Splitting of countries has as much improvement as getting higher population density. A 5 person household does not have less pollution than 4 person household just because they got one person more to share the blame. Similar two countries combined do as much pollution as if they were separated, because physics does not care about borders.

If we go by per capita, the country that contribute the most to the world pollution is a island country with 300 islands and 1700 people. At the same time there are a bunch of oil countries which list as the most green countries in the world because per capita they got close to nothing in pollution per person. If we go outside of countries, the international space station and antarctic would have insane amount of CO2 per capita since only a very small number of highly specialized people living there.

If we want to stop climate change, going to Palau and Luxembourg with remedies will have zero impact. Their numbers at top of the table is only relevant in terms of statistics.