(1) Description of the pattern
Racism is the overt and covert, conscious and subconscious, belief that people of different ethnicities are not inherently equal. As seen in Anglo Americans treatment and view of Africans in the past and the present, a racist assumption of ethnic superiority supports and underlies exploitation, actual and monetary enslavement, and denying basic human rights to those in need.
(2) Why the pattern is good (i.e. bad)
Racism has historically been the internalized belief that Europian Anglo-Americans have used to justify their conquest, capture, enslavement, killing, and rape of Indigenous people and their land. It allows one group, race, of nation to justify their domination of another people while believing that they are "civilizing" them. As a form of dehumanization (see Dehumanization anti-pattern), racism denies that humanity is one species and that what one does to another they do to themselves.