>
> Yes, the laws should be changed, in keeping with changed reality of
> global migration, where workers might grow up in one country, work
> some in another country, work some more in yet another country, and
> retire at home or in yet another country. There ought to be
> multilateral agreements that allow workers either to transfer credits
> (for having paid into pension and health care systems) to the systems
> of their countries of residence or draw upon multiple countries'
> systems.
There are such agreements. They're called "totalization agreements", I think. Obviously they have to be established on a country-by-country basis and I'm not sure how many countries the US has them with.