The Conservative worldview is the cause of almost all human conflict

[Wounded Bear]

2. People are naturally tribal in nature...

They will congregate and cooperate with like minded people and yes, people who "look" like themselves.

Progressives try to overcome these ingrained character traits. They will try to ameliorate differences and protect people from those who do violence based on them. Progressives tend to consider feelings of "superiority" based on ethnic/racial differences to be indicators of character deficiency or even mental illness.

Conservatives, and especially the extremists that are driving the dialog currently, tend to expound on and exploit these character traits. While they may not actively encourage violence, they are often more tolerant of violence based on ethnic differences as it "proves" their theories. To them, everything tends to he hierarchical, so it is natural to assume one race/ethnicity is superior to another.