Racism, ethnocentrism, religious intolerance, and other forms of bigotry all share a common, significant problem no matter to whom or by whom they are applied. What is this problem? They all divide people and encourage treating people not with compassion as humans, but as groups.
Indeed, they cause a separation in the mind of "us" and "them". "They" are not the same as "us". "They" are less human, dehumanized. "They" are not "humans"; "they" are "'[insert label here]". This opens the door for suspending compassion towards our fellow humans. You aren't killing a child; you are killing a Jew/Muslim/Christian/other-“they”-category. You aren't depriving a human of rights, you are treating a woman like a woman. You aren't persecuting a person; oh no! you are ridding the world of another heretic/witch/etc.
This mindset leads to behaviors that we would otherwise describe as unthinkable and beyond consideration. We have the capacity to treat a member of a dehumanized group in ways we would never treat a human. Acceptance of this mindset leaves us open to indoctrination and manipulation by charismatic leaders who are unscrupulous in their pursuit of their agenda. Indeed, even politicians without spectacularly horrific agendas take advantage of these separations every day.
Humans often do unspeakable evils, and these evils need to be stopped. This doesn't mean we have to tolerate those whose actions harm others. This doesn’t mean we sit in understanding of the person and fail to address, counter, and stop the harm the person is causing. This doesn’t mean that we have to agree with every different viewpoint on this planet. It doesn’t mean we cannot recognize differences with each other.
It does mean, though, that instead of seeing people by their labels - “Jew”/“Muslim”/“American”/”Christian” – we begin to see them as humans who happen to have that corresponding trait. It means that we need to make an effort to recognize and view each person as an individual human with rights and value, and apply laws and standards equally to each. It means that we need to assess people based upon their actions and the content of their character, and not their membership in a labeled group.
What does this mean for me as an individual? This means that I don’t accept or excuse someone harming others just because that person says he/she is one of the “we” and the victim is one of the “they”. It means I denounce a person who acts in such a manner and claims to represent a group I can be identified with. It means that if someone harms me, I hold that person and any other involved individuals responsible for the injury, not all members of any group that the person can be identified with. It means that I cultivate friendships and connections with people on the basis of who they are, not how they can be stereotyped and labeled.