All in all, I consider the US tax system to be comparatively progressive in structure, e.g. soak the rich, yet perhaps less tax as a percentage of national income vs. say some European countries which soak the middle class through VAT. In the USA, the rich are fighting back politically, as a recent court decision permits corporations to contribute funds to political campaigns as if they were individuals, enabling the so called 1% to punch well above their weight so to speak when it comes to electing low-tax officials.
The US Tax system is very progressive. According to IRS statistics, 95% of all the tax revenue they collect comes from the 5% of taxpayers with the highest income.
Because the tax code is so convoluted, however, the actual revenue collected is nowhere near what tax rates would seem to suggest,.
From the mid 1940s until 1963 or so, the highest marginal tax rate was around 90% (compared to the current 39%), but throughout that period, and even after taxes were slashed severely, first by legislation introduced by JFK, and later by Reagan, the IRS has never collected more than 21% of GDP in tax revenue. The worst year, I think, was 1950, when the tax rate was ~90%, and we collected 14% of GDP in taxes. The best was 2000, when we collected 21% of GDP in revenue with a marginal tax rate of 39%.
