> Taxation in the States is at an all time low
Not true in 2014.
Obama raised a number of taxes for the top bracket: Ordinary income: 35% -> 39.6% Capital gains: 15% -> 20% Medicare tax: 1.45% -> 2.35%
Meanwhile in California: 10.3% -> 13.3%
Marginal taxes and the top for residents of California are: 39.6+2.35+13.3 = 55.25% The number is similar for New York City.
You have to go back to the Reagan's first term to find higher tax rates.
Now all we have to do is wait for the growth.
Taxation in the States is at an all time low, and a handful of decades ago the US has much higher taxes at the top and much bigger growth. So there's also plenty of historical evidence supporting the case for redistribution.
There are also a number of moral arguments (which I think are much stronger).