I think the equivalent, Unblinking, might be asking a group of, say, devout Catholics to trample on an image of the Madonna and Child in order to be given a basket of bread. Remember, the worst sin these transhumans can imagine is abandonment and exile. That's worse than killing someone, to them. Allowing John to go alone is equated to exile/abandonment in the leader's head.
That comparison doesn't work well for me.
1. Old John was going to leave of his own choice.
2. The leader's responsibility is to her people. If everyone thought this perilous journey was worth certain death, then fine. But she talked them into it, and she's the leader, so she carries more responsibility.
3. They said in the story that condemnation to loneliness was their worst crime, but they werent nonchalant about their own deaths when it came down to it. Perhaps that is "officially" the worst crime in their idealisms, but it didn't seem to click with their behavior. She is given the choice between two crimes: abandonment and the murder/suicide of everyone she knows. She chose the latter.
I'm not sure how to suggest alterations to the Catholic analogy to make it fit better with how I see it, because the story is such an extreme case. The basket of bread is not a good choice for incentive, because a small portion of food as an incentive for one person to trample the Madonna, is not at all the same as depriving your tribe of any chance at survival to satisfy the nostalgiac urges of one man.
Hmmm... I'm just not sure that there's a concrete example that has to do with Catholicism. More apt would be a nomadic tribe on earth choosing to travel into the Antarctic wastes because the oldest member of their tribe wanted to go to the South Pole and you didn't want him to die alone. If someone wants to volunteer to travel with him, good for them! But convincing your whole tribe to travel to their doom on a whim is irresponsible and stupid. This is a criticism of the character, not the story. I don't find it unbelievable that a leader would make that choice, but it does make her unworthy to be a leader.
Okay, back to the Catholicism. Since I can't come up with a realistic example, how about a silly example? Imagine one hundred Catholic space colonists who've crash-landed their ship on a planet. The planet is apparently devoid of life, but able to sustain it. They have a few food rations, but they'll only last a few months. Their only hope of sustainable life is to grow crops. They have seeds, but they're contained within a pinata which has the unfortunate shape of the Virgin Mary with Child. Some colonists think they should bash the thing open, get the seeds, start the crops, and though their survival is not assured, they will at least have a chance. Others would never desecrate the sacred pinata, and would rather die on the planetary wasteland than to break it open. Old Bob, in particular, refuses to entertain the notion of breaking the pinata. They look to their leader to decide what to do. In this story, she takes pity on Old Bob and talks everyone else into wandering the wilderness. And they happen upon an abandoned starship filled with ample supplies, rations, and lots of good seeds so it all turns out okay, hooray for them. But she could never have foreseen that it would turn out so well, barring some kind of psychic ability, it was still a stupid decision, tantamount to murdering her faithful parishioners. Better decisions would have been:
1. For those who will not see the pinata broken, or who wish to travel with Old Bob so that he needn't die alone, allow them to take a portion of the remaining food rations and wander the wastelands until their certain death--because they have not caused nor benefited from the desecration, they can die with clear consciences. The rest of the colonists will stay behind, break the pinata, and survive as best they can--perhaps with troubled hearts, but they did what was necessary to survive.
2. If the leader wishes to make a stance as an example to the others, she can resign leadership and choose to travel with Old Bob herself. That is both reasonable, and responsible. She makes the decision for herself and sets a moral example, but allows others to make the decision for themselves.
I like this example of the Catholic view better, though it is obviously unrealistic in its origins, more of an allegory than a real life example. In this case it is not a small portion of bread at stake but the survival of everyone you're responsible for the safety of. And it's not a single choice made by a single person, but the entire group able to make their own choices (though the leader holds leadership, she does not control their minds).