Universal morality and individual choices....an unresolved tension in human conflicts

Robert Wright, writing in the October 23, 2013  edition of The Atlantic a review of Joshua Green's Book, Moral Tribes: Emotion, Reason, and the Gap Between Us and Them, outlines a thought experiment that, he says, has gained credence and visibility. The experiment goes like this:
The thought experiment—called the trolley problem—has over the past few years gotten enough attention to be approaching “needs no introduction” status. But it’s not quite there, so: An out-of-control trolley is headed for five people who will surely die unless you pull a lever that diverts it onto a track where it will instead kill one person. Would you—should you—pull the lever?
Now rewind the tape and suppose that you could avert the five deaths not by pulling a lever, but by pushing a very large man off a footbridge and onto the track, where his body would slow the train to a halt just in time to save everyone—except, of course, him. Would you do that? And, if you say yes the first time and no the second (as many people do), what’s your rationale? Isn’t it a one-for-five swap either way? (from The Atlantic website, November 13, 2013)
Whether it's a one-for-five swap either way, there are people who would, by their response, prefer to pull the lever than  to push a man to his death. There is a different kind of agency, and thereby perceived responsibility, and also one has to assume, degree of guilt, that accompanies each of these options. Pulling the lever is clearly more "detached" and more objective than putting a hand on a person's body and shoving that person to his death. And, if one follows some of the logic that researchers attach to the experiment, there is a different level of emotional response to one choice over the other.
The Wright piece is couched in terms of why humans are in conflict, and whether there are ways to lower the level of conflict, given the innate nature of the human being, as well as the human types of organization. Green, according to Wright, seems to think that we are closely tied to small groups, from whom we collect our conventional perceptions and attitudes, and that only when these groups are competing for a common finite resource, does conflict arise.
From the Robert Wright Piece in The Atlantic:
So if we’re such moral animals, why all the strife? Joshua Greene’s answer is appealingly simple. He says the problem is that we were designed to get along together in a particular context—relatively small hunter-gatherer societies. So our brains are good at reconciling us to groups we’re part of, but they’re less good at getting groups to make compromises with one another. “Morality did not evolve to promote universal cooperation,” he writes.
Greene seems to think this wouldn’t be such a big problem if we were still living in the Stone Age, back when sparse population meant that groups didn’t bump into one another much—and when, anyway, a neighboring village might share your language and your culture and maybe even include some of your kin. But the modern world smushes groups together, and to further complicate things, they have different values. Greene writes:

Many Muslims believe that no one—Muslim or otherwise—should be allowed to produce visual images of the Prophet Muhammad. Some Jews believe that Jews are God’s “chosen people” and that the Jews have a divine right to the land of Israel. Many American Christians believe that the Ten Commandments should be displayed in public buildings and that all Americans should pledge allegiance to “one nation under God.”

This fact—that different groups view life “from very different moral perspectives”—is what Greene calls the “Tragedy of Commonsense Morality.” He opens his book with a parable in which different tribes subscribing to different values can’t get along and says, “They fight not because they are fundamentally selfish but because they have incompatible visions of what a moral society should be.”
If this diversity of moral codes is indeed the big problem, one solution suggests itself: get rid of the diversity. We need “a common currency, a unified system for weighing values,” Greene writes. “What we lack, I think, is a coherent global moral philosophy, one that can resolve disagreements among competing moral tribes.” He is proposing nothing less than the moral equivalent of Esperanto.
Green offer utilitarianism as his choice for a universal moral code.
However, at the same time, a writer on religion, Karen Armstrong, has been working with others, "on a major international project to launch and propagate a Charter for Compassion, created online by the general public and crafted by leading thinkers in Judaism, Christianity, Islam Hinduism and Buddhism" (from the cover of Armstrong's book, The Case for God)
What seems to have happened, far to often, at least in western 'Christian' circles is that the meaning and import of words and concepts has so radically changed from their original that we have in fact distorted our own religious belief and practice. In addressing the question of belief (and its corollary, practice based on belief) Armstrong writes this:
Those who beg him (Jesus) for healing are required to have "faith" before he can work a miracle, and some pray: "Lord, I believe, help thou my unbelief." We do not find this preoccupation with "belief" in the other major religions. Why did Jesus set such store by it? The simple answer is that he did not. The word translated as "faith" in the New Testament is the Greek pistis (verbal form pisteuo), which means "trust, loyalty; engagement; commitment. Jesus was not asking people to "believe" in his divinity, because he was making no such claim. He was asking for commitment. He wanted disciples who would engage with his mission, give all they had to the poor, feed the hungry, refuse to be hampered by family ties, abandon their pride, lay aside their self-importance and sense of entitlement, life like the birds of the air and the lilies of the field, and trust in the God who was their father. They must spread the good news of the Kingston to every in Israel--even the prostitutes and tax collectors-- and live compassionate lives, not confining their benevolence to the respectable and conventionally virtuous. Such pistis could move mountains and unleash unsuspected human potential. (Karen Armstrong, The Case for God, p.86-87)
It seems that our obsession with our own "perfection" may be distracting us from compassion, benevolence especially to those don't fit our version of "respectable" and "conventionally virtuous"...and that  kind of human compassion will never become realized or realizeable unless and until we shed our protective armor of clinical and sterilized pristine sense of language reduced to a degree which renders impossible our human capacity to deliver. Commitment, a highly subjective word, not easily measured, is much more threatening for those who need a statement of "belief" by which to measure those they are willing to include in their inner circle...and if one is uncertain, or sceptical, or unsure, there are far too many cells of so-called Christianity who would far to readily dismiss those they consider "of little faith" yet their own, that is the faith of the judges is unshakeable. Their exercise is really one of "gate-keeping" on behalf of God, certainly not one of commitment and practice of a life-giving, compassionate commitment.
As for the thought experiment, while neither option is easy, it would seem to be highly unlikely that, unless and until I was actually placed in a situation faced with either set of options, in which I had literally no time to react, that I would clearly know how I would react. I might become completely  discombobulated, and so vulnerable and confused that would be unable to react. What about you, dear reader?