Over 2,000 years ago, Julius Caesar is said to have coined the phrase divida et impura – Divide and Conquer – to describe a strategy for overcoming and conquering foreign lands. Incredibly, this expanse of time and history has not taught the average person to see the tactic when it is employed, and resist it.
I am not apt to describe what is human nature, for you can hardly observe the behavior of humans in captivity and claim to understand their nature. But perhaps it is a malfunction caused by the human ego to separate this from that, black from white, up from down, right from wrong; to see the world in a matrix of dualities. Of course, this is useful at times, but it can cause us to lose touch with reality when we confuse the world as it is with the world as we think about it.
There are many tactics used to advance the divide and conquer agenda, but most fall within the circle of what might be termed identity politics. Man; woman. White; colored (et cetera). Christian; Jew; Muslim (et cetera).American; Russian; Mexican (et cetera). Left; right; conservative; liberal. All of this causes us to confuse reality by viewing it through some lens of cultural or ideological point of view. You don't see things as they are, you see them as you think you're supposed to see them according to whatever identity you're currently clinging to.