Ironically I read Father Richard Rohr's daily email today just before reading your article. He wrote about how exclusion works (especially from a religious context) and I thought it would make a nice addition to what you wrote - kind of an understanding of why some religious people go to exclusion (not an excuse for it). Here's what he wrote -

If our egos are still in charge, we will find a “disposable” person or group on which to project our problems. People who haven’t come to at least a minimal awareness of their own shadow side will always find someone else to hate, fear, and exclude. Hatred holds a group together much more quickly and easily than love and inclusivity, I am sorry to say.

Sadly, the history of violence and the history of religion are almost the same history. When religion remains at an immature level, it tends to create very violent people who ensconce themselves on the side of the good, the worthy, the pure, the saved. They project all their evil somewhere else and attack it over there.

Something has to be sacrificed. Blood has to be shed. Someone has to be blamed, attacked, tortured, imprisoned, or killed. Sacrificial systems create religions and governments of exclusion and violence. Yet Jesus taught and modeled inclusivity and forgiveness!

As long as we try to deal with evil by some other means than forgiveness, we will never experience the real meaning of evil and sin. We will keep projecting, fearing, and attacking it over there, instead of “gazing” on it within ourselves and weeping over it.

The longer we gaze, the more we will see our own complicity in and profitability from the sin of others, even if it’s the satisfaction of feeling we are on higher moral ground. Forgiveness demands three new simultaneous “seeings”: I must see God in the other, I must access God in myself, and I must experience God in a new way that is larger than an “Enforcer.”