Cumulative carbon dioxide emissions are the dominant driver of climate change. These began rising during the Industrial Revolution (especially after 1850)—which means richer countries like the United States, which made an early transition to a heavily fossil fuel-based economic system, have an outsized role in contributing to the climate impacts we see around the world today.
Both in terms of cumulative emissions, and current per capita emissions, richer countries rank high. Conversely, low- and middle-income countries have lower cumulative historical emissions and per capita emissions. Even within countries, it is the relatively rich that are most responsible for a majority of carbon emissions.