It wont happen with the US in its current form. Climate change is absolutely the only hope now. Ideals such as American exceptionalism are key parts that can't be changed. American democracy is very close to a real religion and its not subject to external pressure from other countries or cultures.

The only way forward is destroying the very fabric of American life, ideals and society in a way that forces specially the younger generation to realize they must change the world otherwise they'll die rather soon. However even that is of questionable hope, younger generations are already disillusioned today. Everyone already understands they'll never own a home or even retire. Humanity as a whole is already behaving like frogs in the boiling water. Everyone knows of the disaster or realize something is going wrong, everyone is unhappy and miserable, yet there is no alternative, ever.

Sadly though we only have a few years left, none of this will actualy happen anyway because people will think of the shortest path to survival. Ecofascism and expansion of American influence while everyone else gets crushed or do their own little bit of carving up the global south for themselves(BRICS is somewhat like this).

So I'd say it wont ever happen, but if it could happen, climate change seems like the only real strong enough force to change American society to the core. However even assuming that I also can't jump to wishful thinking that humanity will survive climate change and we will emerge as communists as a result, rather the opposite realy so idk.