Graph below from Piketty’s book, that was already discussed a few times in this blog. The graph shows wealth (not income) of the top 10% and 1% in Europe and the US. Wealth inequality did not increase as much as income inequality in the late 20th century.
Of particular interest is the fact that the US has been since the late 1960s more unequal than Europe. This together with the fact that there is not significant mobility in the US should shatter the myth about the American dream and the idea of the land of opportunity.
PS: For more on mobility go here, where Saez (a co-author of Piketty), and others show that particularly in the South income mobility in the US is lower than in other advanced economies. Also, this paper shows that mobility is lower in the US than in the UK and Nordic countries.