What is wrong with the Christian Identity Groups? Are they white supremacists?
Yes.
I'm lazy so copy pasta from wiki.
Christian Identity (also known as Identity Christianity[1]) is a white separatist interpretation of Christianity which advocates the belief that Germanic peoples (including Anglo-Saxon, Nordic peoples) and people of kindred blood are the descendants of Abraham, Isaac and Jacob and hence the descendants of the ancient Israelites (primarily as a result of the Assyrian captivity).
CI is not an organized religion; instead, it is independently practiced by individuals, churches and some prison gangs.[2] Its theology promotes a racial interpretation of Christianity.[3][4] Christian Identity beliefs were primarily developed and promoted by two authors who regarded Europeans as the "chosen people" and Jews as the cursed offspring of Cain, the "serpent hybrid" or serpent seed (a belief known as the two-seedline doctrine). White supremacist sects and gangs later adopted many of these teachings.
Christian Identity dictates that all non-whites (people not of wholly European descent) on the planet will either be exterminated or enslaved (Dominion Theology) in order to serve the White race in the new Heavenly Kingdom on Earth under the reign of Jesus Christ.[citation needed] CI doctrine states that non-whites can never achieve salvation or paradise, instead it states that only "Adamic" (white people) can achieve salvation and paradise. Many adherents are Millennialist.
Adherents of Christian Identity refer to non-whites as "mamzers" or "tares".
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Christian Identity is a major unifying theology for a number of diverse groups of white nationalist Christians. It is a belief system that provides its members with a religious basis for racial separatism. Herbert W. Armstrong is inaccurately described by some of his critics, as well as by supporters of Christian Identity, as having supported Christian Identity, due to his belief in a modified form of British Israelism, and the fact that during his lifetime, he propounded observances favoured by many Christian Identity groups, such as seventh-day Sabbatarianism and biblical festivals. The Worldwide Church of God which Armstrong founded did not subscribe to the anti-Semitism commonly espoused by the Christian or Israel Identity groups but instead adhered to the traditional beliefs of British Israelism; i.e., the belief that modern day Jews are descendants of the Tribe of Judah whereas the Anglo-Saxons, Celts, Danes, etc. are descendants of the remaining Ten Tribes of Israel formerly known as the Northern Kingdom.
Christian Identity groups include "The Covenant, The Sword, and the Arm of the Lord", the Phineas Priesthood, the Oklahoma Constitutional Militia, also known as The Universal Church of God. Christian Identity is also adhered to by other groups such as Aryan Nations, the Aryan Republican Army (ARA) and the Patriots Council, Church of Jesus Christ Christian, Thomas Robb, LaPorte Church of Christ, Mission To Israel, Folk And Faith, Jubilee (newspaper), Yahweh's Truth (James Wickstrom), Church of Israel[17][57] and Kingdom Identity Ministries.
South African branches of Christian Identity have been accused of involvement in terrorist activities, including the 2002 Soweto bombings.[58]
Other Christian Identity groups include the Heritage Christian Church and the Legion for the Survival of Freedom.