Actually, I believe you are the one who has it upside down. Understandable, as you've probably been raised and lived in the bubble of a controlled environment amongst a specific control group. But, having spent most of my adult life in the military surrounded by individuals from every corner of the country, from every race, gender, nationality, economic status, religion, and political party. I can assure you, the psychological humanity and core division you speak of is minimally measurable, if it exists at all. You see, when you look up and down military ranks, you will see noticeable and vast differences...but, you will also find the two main principles they all have in common: 1) The US Flag on their shoulder; 2) The belief the soldier on their right and left will fight and die for them.
A great country needs common principles to bond and rally around. Politicians know the quickest road to power is division within the electorate, using identity politics and pitting individuals differences against each other.
I have never seen my biracial children at their classmates throats because of their white side or brown side...hell, no one in their peer groups even notices it or brings it up. Rather, I have clearly seen politicians and their acolytes in education with grotesque political motives jamming it down their throats.
All politicians use division and fear to generate power, but it is leftist who are leading the way in destroying our national unifying principles and identities.
It only takes a superficial amount of Wisdom and real personal experience to understand this.