White supremacy
White supremacy is an ideology which asserts that white people (such as Aryans) are somehow "better" than people of other races. These feelings can range from mild (personal bigotry) to extreme (advocating political and social dominance for white people). White supremacism is often associated with Nazism.
White supremacism as a movement in the United States was most recently closely associated with four groups, Aryan Nations, the National Alliance, the Church of the Creator, and White Aryan Resistance, as well as many smaller, often short-lived groups. All four of these groups peaked in the 1980s-90s and are now in disarray. Aryan Nations, in particular, attempted to unite disparate elements of white supremacism around the Christian Identity belief system. Another group, the Ku Klux Klan, which has existed in some form since Reconstruction, is also closely associated with white supremacism.