It's not merely a difference of opinion, but one of several ongoing attempts to return "ambient" white supremacy to its former status of "official" white supremacy--like that preached by Teddy Roosevelt without apology or prevarication because it reflected the fundamental nature of this society. The US is and has always been a white supremacist nation. It's social, political, economic, legal and educational institutions are inherently white supremacist. Most white so-called "liberals" can no more hold a conversation outside the limits of their ideological talking-points with a black or brown person than a "conservative" can tolerate being disputed by one. An "honest conversation about race is not allowed" because most white Americans don't want one. The very idea threatens their illusion that they're "the good guys". That's why the first thing they do when someone points out the enduring white supremacist nature of their institutions is to howl "WAAAAAAAAAAAAAAAAAAAAY-cist"!!!