Fascism is a reaction to the loss of status and, secondarily, opportunity. Historically this is a direct descendent of feudalism or rule by warlord.
We know it in the 20th century, initially, as fascism that blended cronyism with militarism. This also produced the modern imperial rule defined by the US based on control by the military industrial complex.
The levels of corruption grow until competent people are driven from government service and only selfish opportunists remain. That quickly descends into police state chaos supported by a permanently angry minority supporting their own subjugation. The US is now at that stage and may not be salvageable.