DISCLAIMER: This map is made purely for entertainment purposes and I do not support any ideas, entities, or persons described therein.
This map is a mishmash of various ideas that I've had floating around. North America is the star of the show, and that big green blob is the American Free State, a white nationalist state created through a long, arduous process starting from the early 1990s.
Basically the anti-globalization and anti-immigration movements of the time do not peter out, but instead take a radical and darker turn, and their proponents focus on setting up roots throughout small Midwest and Dixie towns. They also become increasingly prevalent in the police and military, forming a "Deep State" akin to what we see in IRL Turkey or Pakistan.
Then one fine day in the 2030s (not so fine, as by this time political polarization has reached horrific levels), the President and senior officials are brutally assassinated and a nationalist dictatorship is declared. California, Cascadia, and South Florida quickly declare their independence, which the nationalists are quite happy with. Various southwestern communities swear their allegiance to Mexico instead. The urban-liberal Atlantic Seaboard holds out with the hope of returning to the old order, but is unable to make a move, and eventually separates peacefully. Meanwhile the southern states are party to a horrific partition that hearkens back to what happened in South Asia a century ago.
The new American Free State is not a very nice place to live, being statist, protectionist, authoritarian, and quite poor. America's other successor states are doing quite well.
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I'm putting a lot of effort into the rest of the world too. Will be a geopolitically interesting place.