That's a point, although some countries have been relatively rich all the way through for the last few hundred years -- like Britain or Netherlands. But generally you're right, the poor countries are badly undercapitalized to soak all the excessive labor supply.

I have also been thinking of an intermediate option for the international organizations: move WB to Calcutta, move IMF to Buenos Aires, move UN headquarters to Jerusalem -- I understand that this would lead to enormous havoc in those organizations, but at least they'll be working in an area where their mandate is relevant the most, and have a much stronger committment to provide high quality service.