How some Christians have threated others in USA

I do believe that Christian principles and teachings helped with the foundation of this nation. Afterall, those who first came did so because of religious persecution in their homelands. The founding fathers, in their infinite wisdom, chose not to set a national religion or language, after all, the search was still on for "a more perfect union." Somewhere along the road to the search for a "more perfect union" some religious denominations lost their way and persecuted some who didn't quite believe the same as they did. And so society, denounced the Catholics, Jews, Mormans, and others. Today, that search for a perfect union is still not achieved, as some Christians do not want Islam and others. In fact, look at our history of how we have treated others...blacks brought as slaves! Irish, Mexicans, Asians, treated worse than dogs. When will we learn?