"European countries generally tax consumption rather than income, though someone here pointed out that some countries might also impose a very low flat tax on income as well. "
Don't agree. Income tax is around 50% or even higher. Sales tax (VAT) is much lower.
I agree with regard to the topmost income bracket in some EU countries. I think the German top bracket is near 40-5%. But of course most countries use a progressive marginal rate system with much lower marginal rates in the lower brackets. Details are available, by country, via Wiki, for those who care to take the time. I would say, however, that, in general, the federal consumption (VAT) taxes are in the range 8-20% in the EU countries. But please check this out for yourself, as I am no expert on EU taxes.
What is important, from the U.S. tax base perspective, is that currently, when all federal taxes on individuals are considered, including medicare and social security, the net amounts paid as a percent of income is, on average, almost perfectly flat, despite the absurdly complex, U.S. tax code. For example the cohort that earns 3% of the total of U.S. income pays ~3% of the total of individual taxes, the cohort that earns 20% of the total U.S. income pays ~20% of the total of individual taxes, etc. Seen from this perspective the U.S. federal tax structure is nearly perfectly flat already.
What I maintain is that this unseen "flatness" of the real net tax rates has been primarily responsible for the redistribution of income from the middle class to the wealthy over the past 35 years, or so. This is despite some small amount of progressiveness having been returned to the marginal income tax rates subsequent to the supply-side experiment of the 1980s. Assuming I am correct, a purposeful complete flattening of the income tax brackets would exacerbate the redistribution of wealth we have already experienced, leaving even less capital with the middle class and virtually none with the the lower middle class. In my personal opinion this is a highly undesirable situation that can sap vitality from the U.S. economy, and in the worst case lead to civil unrest. No one, including the wealthy, benefits from such a lopsided distribution of capital. A permanent trapping of lower paid workers in the labor class can result! If the lower middle class is to escape from labor to the capital class it must have access to capital. The tax structure must be such that some capital is left with the lower middle class.
