What's behind the current flavor of multiculturalism for some hardcore leftists is hatred of Judeo-Christianity and rejection of its God. This is evident not only in their treatment of observant Christians and Jews (especially their views on Israel,…), but in their attack on science and truth.
In the absence of an absolute, there is no "truth"; there is only "power" and "personal narrative." Thus does good become bad, wrong become right, ugliness come to be hailed as beauty. A human baby in utero is "just a clump of cells." Killing it becomes a "human right." Teaching small children how to perform sex acts becomes "education." A man becomes a woman (and vice-versa) by proclaiming that (s)he feels like one.
Anyone who says otherwise -- first and foremost the God of Jews and Christians -- is the enemy.
Laura Hollis, What’s Behind ‘Multiculturalism’