NEW YORK — The notion of a divide between the rich north and the poor and developing south has long been a central concept among economists and policymakers. From 1950 to 1980, the north accounted for almost 80 percent of global GDP but only 22 percent of its population, and the south accounted for the remainder of global population and 20 percent global income.
But the north-south divide is now obsolete. The dynamic process of globalization has resulted in unprecedented levels of growth and interdependence. However, while this has blurred the old division, new ones have emerged, splintering today’s world into four interconnected tiers.