I think there are universal principles that we should want to understand, but that are not necessarily good for us. We could recognise universal propensities which current cultures can't fully eradicate, which we would want to eradicate if we could. Let's say, a tendency for tribal violence. Or racism.
Mainstream American society finds it easiest to be tolerant when the outsider chooses to minimize the differences that separate him from the majority. The country club opens its doors to Jews. The university welcomes African-Americans. Heterosexuals extend the privilege of marriage to the gay community.