Trading of goods. For example on the southwest coast of British Columbia the indigenous people had a trading network expanding a great deal inland and even more so southward and northward.
The 1896 Supreme Court case which resulted in the "separate but equal" doctrine was Plessy v. Ferguson. Plessy v Ferguson allowed state-sponsored segregation in public facilities, such as bathrooms, public school and transportation. Even when this legislation was scrapped, there were groups in the South still fighting for it to be upheld.
Well, everybody has their own reasons for literally everything. It all depends on what's happened in the person's life. If someone loses someone, or get's hurt, or something they take out their pain on other people, leading them to kill people.
All of this goes under sociology, behavioral science, criminology, victimology, and psychology.
As for hatred, I don't know that people "love" it. People just have a need to be defiant and rebellious.
As for power, people are sometimes control freaks. They need to be in control of all situations. This has to do with how they were treated as a child. If they were beaten, or bullied, they'd like to rise up and become the beater or the bully.
Hope that helps!
