I have an extremely simple analysis.
Leftists (democrats) are only good at proposing really terrible things, and wrecking good things.
As such, they were opposed to civil rights laws when such laws were actually a good idea (pre civil war to about 1960).
And then, they embraced increasing such legislation past the point where it actually did some good. In other words they embraced it only when the situation had been dealt with and further legislation was actually harmful!
It is like being against penicillin right up to the point that the patient is recovering (from doses of penicilling), then demanding MORE penicillin be given to the cured patient - which will kill him.
They are always wrong and destructive.
What simpler way could two political camps be constructed? One, basically right; the other, wrong.
That’s an interesting outlook. I would wonder what deformity a persons mind could have that would lead them to be so destructive, especially towards their own country.