Piketty's 2013 international bestseller, Capital in the Twenty-First Century, makes the case for an annual “global” wealth tax of up to 2% for rich households, adopted by cooperating governments across the world (a “utopian” ideal, he says, for a tax that might first be tried regionally). The book, a 700-page theory-of-the-case on the history and trajectory of wealth inequality, describes a widening gap in private capital “even more worrisome” than the widening gap in income — with accumulated and inherited wealth growing at a higher rate of return than the economy. The result, Piketty says, is “indefinite” wealth concentration, a threat to “meritocratic values” and “social justice.” In the U.S., the book generated a months-long debate among economists, academics, and columnists. But in Washington, even as Democratic lawmakers praised his work, they steered far from the words "wealth tax"

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