I guess the physical fighting of the Civil War ended, but the mindset never did. A population of imperialistic white European descendants who are perfectly content to retain or attain wealth, status, or privilege by stepping on the backs of those who have less status or means of survival.
People with this mindset will fight or hurt anyone or destroy anything that gets in the way of their ability to enforce the pecking order that enables them to they thrive in a way of life they enjoy. And they will justify their cruel or unfair actions and policies to feel righteous or “Christian”
If the Democratic-Republic form of government won’t preserve their privileges and ideals then they will gladly tear it down and install a dictator to force it down everyone’s throats