Our yearning for pan-human solidarity is an absurdity, the absurdity of the human condition, and the most utopian of all utopian ideas is the idea of a Brotherhood of Man: because the human race is not a family, just like it isn’t one big polity. We are stuck with differentiation; there is no metaphor that allows us to redefine humanity as a closer relationship than it is.
Nuts. Firstly, it's no "yearning" to be in solidarity with other humans; it simply is a fact that we are. Language, culture, faith, customs -- these provincial/regional structures only mask the inescapable truth that we all share the same basic DNA. Secondly, why is it better to be cynical than it is to be idealistic? Idealists got us to the moon, for heaven’s sake. Idealists got us the Declaration of Independence and the Constitution. The "Brotherhood of Man" exists implicitly in the phrase, “all men are created equal.” And if we are created equal, then we are all brothers, we are all “citizens of the world.” It’s not just a figure of speech; it’s an ideal. And while we humans — most notably James Poulos with his comments — frequently fall short of the ideal, it does not obviate the need to reach for the ideal. We recognize the universality of being interdependent and united toward a common goal and a greater good for everyone, not just good for one group or nationality or religion.
I can be just as snarky as the next guy, but beneath it all I take nothing away from the humanity of those I snark against.