The US has a very regressive tax system says Nobel Prize Winning Economist

Remember, the low tax rates at the top were supposed to spur savings and hard work, and thus economic growth. They didn’t. Indeed, the household savings rate fell to a record level of near zero after President George W. Bush’s two rounds of cuts, in 2001 and 2003, on taxes on dividends and capital gains. What low tax rates at the top did do was increase the return on rent-seeking. It flourished, which meant that growth slowed and inequality grew.

http://www.alternet.org/economy/nobel-prize-winner-joe-stiglitz-blasts-americas-1-percent-coddling-tax-system?akid=10328.294211.vAYp0J&rd=1&src=newsletter825186&t=13