If you think large pluralities of Chritian churches in the U.S. did not support chattel slavery on theological grounds, you are simply mistaken. I suggest you use Google with an open mind. Start with the history of the Southern Baptist Convention.

Besides, the fact that many abolitionists were Christians does not detract from my point. Many other Christians supported slavery, Jim Crow, and school segregation using Christian theological arguments. Christians argued on theological grounds in the mid twentieth century that “mixed marriages” should be illegal. Google “Loving v. Virginia.” As late as the 1980s, Bob Jones University used Christian theology to support campus segregation and to argue that they should be exempt from the Civil Rights Act of 1969 on religious grounds. The Supreme Court ruled against them. Google “Bob Jones University v. United States.”