We'd probably find that severely disabled babies are quietly executed in most of the world today, perhaps in the West not too long ago. I suspect that we don't do it because we're an instinctively compassionate people (like the rest of the world), but unlike the rest of the world, we can afford them. No doubt Christianity's promotion of the value of human life also has a substantial role.
I'm not an Objectivist, but I think most Objectivists would admit to narrow or rare instances where rational self interests conflict beyond what can be managed by a proper government. They won't admit to that conflict within Objectivist principle's though, absent some kind of rare and unanticipated emergency situation.
Nevertheless, I suspect rational men will disagree much less severely than men who've devoted themselves to separate evangelical religions.
I'll lose the attitude if you will.