Perhaps the real problem facing the whole world´s economy is that economic units have to cross political borders and are thus impeded from becoming the most efficient units possible. National borders are drawn for a whole host of reasons that may be rationale or not but economic units are organic and rationale.
It is instructive to see how the world may be divided by economic units. Obviously the USA, Canada and Mexico form an economic unit. The major trade partner of each is the other. Central America could be a unit with Panama as its hub. The countries of the “Andean Pact” form an economic unit roughly parallel to the Inca Empire. Argentina, Paraguay and Uruguay form a natural economic unit.
The curious case is Brazil which more or less does incorporate an economic unit in one country.
Western Europe is largely within the European Union which based on economic rationales would include Norway, Switzerland and any other small country in the west side of the continent. Funny, Eastern Europe was in an economic unit, the Soviet Union. The divide between Western Europe and Eastern Europe should be the Dnieper River that splits Ukraine in two.
The Middle East was one economic unit under Ottoman rule. And Turkey is still the major power with its ancient rival Iran (Persia) to its east.
Southern Africa including South Africa, Angola, Mozambique, Zimbabwe, Zambia, southern Congo, Botswana, Namibia, Lesotho and Swaziland form a natural economic unit with minerals and mining its main source of income. West Africa could form an economic unit around Nigeria which is the commercial center of the region.
India, Pakistan, Bangladesh, the Himalayan states and perhaps Myanmar form another economic unit. China is the heart of a huge Asian economic unit with Japan still another. Indonesia could aline with others in Southeast Asia and indeed does in the ASEAN pact.
Maybe if the world were divided along these economic “borders” we would have fewer problems. But the reality is that politics rules economics so not much chance of this happening.