The problem humans continually face is our egotism: in order to make the world sensible to ourselves, we treat humanity as if it were a whole comprised of equal and essentially identical atoms, because if they are not nearly identical, our inequality has a purpose and logical cause.
The egotist fears being inferior. He therefore agitates whenever someone else has something he wants or appears to be succeeding where he is not. Therefore he constantly wants to tear down everything but himself, and this pathology propels him eventually toward moralism.
Moralism refers to the habit of passing judgment on things instead of figuring out how to fix them. Moralists do not want functional solutions; they want a good/bad binary where they can categorize everything that scares them as bad, and everything they want as good.
To that end, the morality of the egotist is simple: does this make me look good to others, or not? He simply wants what he wants, and he sees others as a means to that end, so he comes up with some reason why he is a victim and therefore deserves what he wants.
The group is thus held hostage. If they do not give him what he wants, he will never stop, and will keep playing the victim until he lures others to his point of view. Egotists destroy civilizations by insisting on personal agenda that clashes with the reality of maintaining civilization.
Diversity acts like an egoist. By virtue of not being from the founding group, diversity citizens feel alien and act against their society for personal gain, justified under perceptions of victimhood. They tear down culture and other intangibles so that they can feel safe from it.
The far-Right makes a big deal of Jews and Negroes in this context, but in reality, it is true of any foreign enough group. As we see from our current president, the Irish and Italians of previous generations did not integrate and still view themselves as antagonists of the founding group.
Under diversity, morality rejects reality in favor of this victimhood narrative. One can either be the slave or the master, but never simply someone working with the group to advance its unions of goodwill, namely culture and heritage.