In the United States the marginal tax rates (ie, what the wealthy pay for what they earn above a certain threshold ) of the income tax were very high after the second world war. In the recent decades, they declined dramatically.
The debate on this issue has been reactivated as a result of French president
Hollande 's promise to raise the marginal rate of the income tax to 75 % (the
promise has been fulfilled, but for a
very high threshold and for corporations, which has received protests from the
rich, especially football clubs), and the movement "Occupy Wall
Street", which had as one of its slogans "We are the 99 %" , as a
reference to the fact that economic growth in recent decades only benefited the
Apart from the historical evidence, the interesting thing is that the best
economists who have studied this believe that a top marginal rate above 70 % is
desirable, meaning that it is socially optimal,
because contrary to what the right says, it would not create a major
disincentive to wealth creation, and would allow for ambitious distributional
Paul Krugman has repeatedly referred to this in his blog, for example here and here.
There is a very interesting book with articles by some of the leading experts
on the subject (Sáez, Piketty, Diamond) which is the "Occuppy Handbook". It is a very interesting book with articles by leading
economists of the highest academic level that support progressive proposals.
Incidentally, it is interesting that this book does not show any Spanish economist.