According to the Federal Reserve Board, the richest 1% of Americans own 32% of the wealth of America, which is astonishing amount of wealth in those very few hands. When it comes to taxation, and in recognition, that the income tax as initially created via the Revenue Act of 1913, that such a tax was only applicable to, as reported by Wikipedia.org "approximately three percent of the population," in 1913, that it should be thereby acknowledged that at the present time, the income tax has morphed into capturing far more people, than was its original intent. This signifies that America needs to go back to fully recognizing that the most basic reason why an income tax was created, and a progressive income tax in particular, was never to tax the middle class, but rather to apply such taxation upon those people that could well afford to be taxed, that is, the very rich; so that this country would not ever devolve into being controlled by an elite class, that would for all intents and purposes, be separate from the people by virtue of having the money to "boss" and to influence their way via legislation, tax laws, and so on.
At the present time, taxation only applies to income, but does not apply against wealth in and of itself, and in point of fact, because our present day taxation does not tax wealth, directly; the wealth discrepancy between the ultra rich and the middle class of America, is at unprecedented levels, and will not self-correct, unless something of significance is accomplished with our present day tax code, of which, the very best plan, would be to tax the wealth held specifically by the very rich. Not only would taxing wealth, at a progressive rate, which would be applicable only to those that have $10 million or more in wealth be a sound plan in regards to the government being able to receive much needed revenue in order to balance its budget, it would also not have any real material deleterious effect upon the very rich. In other words, having a wealth tax that would begin at .5% and would thereby be capped at 2.5% would be more than enough to bring in billions upon billions of dollars into the coffers of American governance, and while, no doubt, would make the superrich, whine and complain, it would not break them, not by a long shot.
In the scheme of things, it is contradictory to have a progressive tax rate, when such a progressive tax rate, ignores the accumulated wealth of an individual or even that of a corporation. The point of a progressive tax rate is to tax at a higher level those that have more, and it is as simple as that. Taxation is the price that good citizens pay for good governance and a good society, of which, those that are fortunate enough to have bucket-loads of money have an inherent obligation to do their part to contribute back to that society which provided them with the opportunity to make that money in the first place. Those that have more than enough need to be reminded, by the tax code, if nothing else, that nobody is an island, but that all are part of a greater whole.