Economist Gabriel Zucman is concerned about tax laws that contribute to income inequality and opportunity inequality. “There is a tipping point above which inequality becomes detrimental to growth and dangerous to society,” he said. “Nobody knows whether we are far or close from this tipping point, but it is there and it is coming.”
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the U.S. and other large economies should impose economic sanctions on tax havens, forcing them to make up the difference in lost revenue through trade tariffs.

“The idea is that we need to change the incentives [that enable] tax havens to facilitate tax avoidance and tax evasion,” Zucman said.

Then, countries such as the U.S. should reform their corporate tax policies to geographically bind taxable profits to the location of the sales that generated them. For example, he said that if Microsoft theoretically makes 50 percent of its sales in the U.S., then 50 percent of its global profits should be taxed in the U.S.

“It’s very easy for firms to move profits to Bermuda,” Zucman said. “But they cannot move their customers to Bermuda.”

Still, Zucman said he recognizes that the political appetite for curbing tax havens is weak. None of the current crop of presidential candidates — ranging from populists (albeit of opposite political ilks) like Bernie Sanders and Donald Trump to establishment candidates like Hillary Clinton and Jeb Bush — has produced any concrete plan to overhaul the tax system, he said.

via Tax Havens Are Turning The U.S. Into An Unequal Aristocracy.