|Source: Mark Perry|
As this chart illustrates, the US already has a quite progressive tax system on the federal level. Indeed, federal taxation is more progressive than most countries in the OECD. This explains why leftists portray income tax cuts as giveaways to the rich -- given the progressivity of US income taxes, it's very difficult to design any kind of sizeable income tax cut that doesn't provide outsized relief to those with the highest incomes since they bear so much of the tax burden.
The most surprising fact to me was that the effective tax rate is negative for the middle quintile. According to the CBO data, this number was +14 percent in 1979 (when the data begin) and remained positive through 2007. It was negative 0.5 percent in 2008, and negative 5 percent in 2009. That is, the middle class, having long been a net contributor to the funding of government, is now a net recipient of government largess.
I recognize that part of this change is attributable to temporary measures to deal with the deep recession. But it is noteworthy nonetheless, as other deep recessions, such as that in 1982, did not produce a similar policy response.