1) The vast majority of slave traders were European Christians, not Jews.
2) Ony 5% of American Blacks are Muslim. (Pew Research)
3) The history of American political parties is long and complex. Both parties have changed radically over the course of American history. Since the end of the Civil War, almost two hundred years ago, things have changed—a lot—in politics. Please google "history American political parties" to start learning how things have changed (e.g. with FDR and the New Deal), how the parties changed, and continue to change. "Those who do no learn history are doomed to repeat it."