A sane moral person shall not feel responsible for any other person's pain, except when the first person indeed caused the pain by his own actions. And even despite any interference that one may suffer from other people, to claim that the primary responsibility on one person's fate lies in the acts of other people is to deny the fact that one is one's own moral agent. Temporarily denying one's responsibility on one's own fate is indeed to treat one as a child. Permanently denying one's responsibility on one's own fate is indeed to treat one as an animal. Those who deny this responsibility are not one's friends, but one's most mortal enemies.
Why should one be responsible for the fate of other people one has never interacted with? There is no reason, and cannot be one. On the other hand, there is a moral duty of justice, to not actively harm other people, to not violate on their life, liberty and property — or to have compensate them for the trouble. And this basic duty specifically forbids us to sacrifice anyone in the name of any Grand Scheme.