Who benefits? It is not just one class or nation.
Russia and China benefit by having the US be a divided nation with few allies.
Both can extend their territorial reach with little opposition. e.g. the seizure and annexation of Chechnya’s Crimea, China’s action in the South China Sea, etc.
Despots in various countries will be able to hold onto power illegally with no fear of recrimination.
Domesticaly,
Low grade news networks can increase views and revenue by fomenting disagreements about any “either/or” issue, e.g. race, abortion, religion, politics. – I am waiting for the upcoming Android vs. IOS revolution.
Facists can use Hitler’s playbook to rise to power – and stay there.
One thing is certain, by continuing the fight those with the most money will benefit more than the little guys.