This 2017 article includes some terrific analysis of the past and future of global inequality, both within countries and across them.
Examining the “World Inequality Report” — published Thursday by the creators of the World Wealth and Income Database, who include the economists Thomas Piketty and Emmanuel Saez — it is tempting to see the rising concentration of incomes as some sort of unstoppable force of nature, an economic inevitability driven by globalization and technology. The report finds that the richest 1 percent of humanity reaped 27 percent of the world’s income between 1980 and 2016. The bottom 50 percent, by contrast, got only 12 percent.
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And yet, a careful examination of the data suggests there is nothing inevitable about untrammelled inequality. Take China and India, developing countries of billion-plus populations playing catch-up to pull themselves out of poverty. Incomes have become much more concentrated in both. But China’s economic strategy has delivered much more growth at a lower cost in terms of economic disparity. Comparing Europe with the United States and Canada offers similar contrasts.
Policy, it turns out, matters. More aggressive redistribution through taxes and transfers has spared Europe from the acute disparities that Americans have grown used to. Unequal access to education is helping reproduce inequality in the United States down the generations. On the other end of the spectrum of development, China’s strategy based on low-skill manufacturing for export, and underpinned by aggressive investment in infrastructure, has proven more effective at raising living standards for the bottom half of the population than India’s more inward-looking strategy, which has limited the benefits of globalization to the well-educated elite.
https://www.nytimes.com/interactive/2017/12/14/business/world-inequality.html