Ku Klux Klan. The Aryan Nations. The American Nazi Party. They are there because there are millions of Americans that believe in their message of white pride. The African American population is growing and Americans are now a mixed group of people.
Black people are white people's neighbours, doctors, friends.
The answer is simple. Racists from many years ago raise their kids in clans and white supremacy groups and teach them the ways of hatred. The Ku Klux Klan has been around since the end of the civil war. It is a roller coaster of a history. The clan, who is notorious for its violence, has a relatively innocent beginning.