Why is there constant division in the country between left and right? IMHO it is fundamentally about positivity vs. negativity.
Liberals and democrats are people who wake up negative, asking "What's wrong with this situation?" They want to complain about everything, tear it all down to nothing, and replace it with some centrally planned, fake monstrosity in the name of "PROGRESS";
...while conservatives and republicans wake up positive, asking "What's good about this situation?" They want to thank God for how great everything is and to CONSERVE the good things we have built from the grass roots up, as humans on an abundantly rich planet and as Americans in an abundantly rich country.
We're of two fundamentally different mental paradigms: one focused on being negative, hateful, divisive, hopeless and miserable; the other focused on being positive, loving, unifying, hopeful and happy.
It's nothing to do with race, religion, gender, etc. The just left wants to "progress" from what they feel is mostly a bad deal; while the right wants to "conserve" what we see as already a fairly good deal.
Also pay attention to the inversions of linguistics. Communists root is community. Liberal is liberty. Both belief systems are the opposite of what they define and tear both apart. Take "communism". A community is a group of people, each providing for the needs of the community. The baker bakes bread, the farmer raises food, the carpenter builds. A functioning community is a threat to the system of control because it is independent. The last thing they want is to do is stop looking left and right and look up at the one pulling the strings.