I wanted to use enemies that nobody could sympathize with, so I decided to make Britain/Brittany get involved with Y'all Queda lol.
I imagine there'd be a ton of foreign actors willing to put men and resources into making sure a balkanized US is reliant on them. For instance, China helped rebuild LA and San Francisco because they would then gain defacto control of the largest port in and out of the union, meaning they could really disrupt the flow of imports and exports if they chose to.
Author Notes:
the SCAR H is from tarkov, and it's been a legitimate blast to use it. thanks to seraphim for the model!