Isolated extremist groups can develop and maintain prejudices despite national norms.

Evidence

Thus, for example, extremist groups, such as the Ku Klux Klan or other white-pride groups, Black separatist groups, and secessionist movements persist in the US, despite their deviation from the culture-at-large. Different subgroups have their own prejudices, and people who are part of the local culture will share the local culture’s values. By limiting their contact with the rest of the culture, the prejudices of extremist groups can persist and even flourish (Myers & Bishop, 1970). — , Rudman, Laurie A - On the Nature of…, 1912