"Understanding" is alot like "Love" in this schema.
Most people think of [either] as something inside one's mind which guides and informs their actions. [Either] is really more of an act, a verb. It's moreso something you have to get up out of your chair and do. It's not that you will intrinsically [either] a person that you meet, you'll have to go out of your way to actively [either] them.
Point being: you won't look at a total stranger and understand them. If you encounter a young black male (I could only make it through like 1/4 of your essay OP so maybe something super cool happened after the young guy called you by what you consider to be a overly familiar colloquialism) and you had a DESIRE to understand him, you'd then have to do some things like talk to him and perhaps meet with him on a future date. You may have to do some of the things he does and consume some of the same media. To lay eyes on a human and say "I DON'T understand" is more like saying "I DON'T CARE TO understand". The lack of understanding is a given upon literally the first look. From there either you'll choose to make the effort or you'll throw up a barrier to understanding (which in this case involves nothing more than KIM).
So it's not that all black people in the world should understand each other, it's that we should all WANT to understand each other and we should all TRY to understand each other.
Why try? Simple. We are despised on this Earth and if the day comes where you need to group up for protection - some apocalyptic shyt - I GUARANTEE you that no other group will have you. Even if there are seven white liberals in a group of 100 whites that wish they could help, the choice will be between the seven of them breaking off from the rest of the group to protect your black ass, or them just feeling bad after they cook and eat you. They gonna eat you breh. 10/10.
