The third option is more likely: The USA will have a civil war, and be unable to go to war with Russia or China, and Russia and China will expand, and the question will be the muslims, with whom the west, russia, and china are already at war.

https://www.quora.com/Which-war-is-likely-to-happen-USA-goes-to-war-with-Russia-or-USA-goes-to-war-with-China