What difference does it make whether globalization hurt "the american worker" more than some people estimated? What really matters is whether it hurt them more

What difference does it make whether globalization hurt "the american worker" more than some people estimated? What really matters is whether it hurt them more than it helped. That may well be the case, but it isn't obvious. Also, what about "the non-american worker"? Did it hurt them more than it helped? Is there a comparative disadvantage? Also, why the focus on workers? What about the young, the sick, the elderly? Could an aging society's welfare be improved by being shielded economically from younger societies?