The USA has seen a fall in CO2 emissions

Since WWII, the USA's emissions have reduced by approximately 10%.

The reductions have come from a range of sectors such as transportation and energy use, and the impact of "stay-at-home" measures during the Covid 19 pandemic in March and April 2020, had significant impacts, even over such a short time period.

Transport has seen the biggest decline and with less energy being created from the burning of coal, this has also impacted on emissions. Coal is now the 3rd source of power, despite it being the dominant source for many years.

For more on this story, check out the following article:

Climate change: US emissions in 2020 in biggest fall since WWII - BBC News