I'm not sure I would describe Stellantis as a US carmaker. The majority of its marques are European, and it's headquartered in the Netherlands.
They make most of their money in North America.
https://www.statista.com/statistics/1297320/net-revenue-stel...
Assuming Dodge Ram pickup trucks and Jeep SUVs are the highest profit margin product they sell, the US might be its most lucrative market.