You're still thinking in terms of 19th century paper-based processes when you attempt to estimate globally integrated wealth in terms of a nationally fragmented paper-based information system ($). Also, GDP is not indicative of net wealth, as it is a measurement which implicitly asserts the broken window fallacy.
Over the long term, breaking down these legacy barriers to trade and freedom of movement would necessarily uplift everyone economically by principle of synergy.
Synergy: the interaction of elements that when combined produce a total effect that is greater than the sum of the individual elements, contributions, etc.
>I'm going to give you an important kind of a picture. I hear a lot of people say "I don't like machinery and technology, it's making a lot of trouble." So we're going to take all the machinery away from all the countries of the world, all machinery, all the tracks and the wires, and the works and we're going to dump it all in the ocean. And you will discover that within 6 months, 2 billion people will die of starvation having gone through great pain. So we say "That's not a very good idea lets put all the machinery back where it was." Then, we're going to take all the politicians from all the countries around the world and we're going to send them on a trip around the sun, and you'll find we keep right on eating. And the political barriers now... scientists say very clear you could make the world work and take care of 100% of the people at a higher standard of living that anyone has ever known despite the increasing population, but you can't do it with the barriers, any more than you can try run a human organism with a wall between the ear, the eye, and the stomach. It is an organic whole, it is total industrialization.
-Buckminster Fuller
>Human history can be viewed as a slowly dawning awareness that we are members of a larger group. Initially our loyalties were to ourselves and our immediate family, next, to bands of wandering hunter-gatherers, then to tribes, small settlements, city-states, nations. We have broadened the circle of those we love. We have now organized what are modestly described as super-powers, which include groups of people from divergent ethnic and cultural backgrounds working in some sense together — surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Many of those who run the nations will find this idea unpleasant. They will fear the loss of power. We will hear much about treason and disloyalty. Rich nation-states will have to share their wealth with poor ones. But the choice, as H. G. Wells once said in a different context, is clearly the universe or nothing.
-Carl Sagan, Cosmos