I'd easily bet on balkanization within 25 years. Certainly inevitable before 2075. All it will take is one Katrina level disaster with people not having access to food and water. Texas snowstorm and COVID were very early previews of what it will look like. Replace the looting for toilet paper with real militias hijacking national guard trucks carrying food.

Realisticaly maybe even under 15 years given 99% chance the current climate trend will continue to worsen.