The United States is effectively run by both individuals as well as behemoth corporations that will not countenance anything that will preclude them from aggrandizing unto them more and more influence, exploitation, and power. For a certainty, money is a form of power, and even those that ostensibly are powerful people in their positions and/or influence, are often, perhaps even unwittingly, move to do things and make decisions that are partly or fully influenced by those that use the effectiveness of money in any and all of its myriad ways and forms, in order to get its specific way.
The only entity that is significantly bigger than today's multinational corporations in which companies such as Walmart had sales of over $500 billion in revenue, in 2018, is the national government. Yet, again and again, large corporations such as Amazon, which had sales of over $200 billion in revenue, did not pay any federal taxes, whatsoever, in their fiscal year, of2018. This signifies that these companies are experts at creating influence in public policy that permits them to escape the taxman, even though these are exactly the entities that have an overabundance of monies that should be performing their part, and even more than their part, to contribute to the good welfare of the people, and to the necessary infrastructure of society.
The purpose of the national government is to represent the common man, and to the extent that it is possible, to help level the playing field for the benefit of the common man. This means that a strong national government protects and defends the common man, so that he is not fodder for colossus corporations or even to rich individuals that effectively dictate to that common man, the terms and conditions of their employment. Further to the point, the reason for a progressive income tax, as well as corporate taxes, in the first place, is for those superrich individuals and super successful corporations to be subject to a fair taxation rate, which thereby provides the necessary funds and means for the national government to keep its fiscal house in order and to serve best, the public, and the public, interests.
Unfortunately, what is only too obvious in American society in the 21st century, is that, embarrassingly, and unacceptably, both the richest corporations as well as the richest individuals, are increasing their wealth collected into their greedy hands at a rate, that is not only unseemly, but unfathomable, in the sense that it is actually occurring, out in the open, and seemingly unopposed. The reason that this is happening, falls to a very large extent, at the feet of this national government, which, in significant ways, aids and augments the richest of the rich so that they can become even richer and even more powerful, by virtue of those governmental taxes, as well as governmental rules and regulations being apparently vacated or gutted in their effect and in their intent, upon those entities.
In the historical scheme of things, the people voluntarily joined together into one body politic, in order to propagate and to formulate a national government which would be beneficial for the people; by providing those people with the necessary means of obtaining their happiness -- consisting of freedom, liberty, justice, and opportunity, equally applied to all. Instead, we presently have a national government that is of, by, and for the superrich for the benefit of the superrich, of which, consequently, so many of the people are unfairly deprived of justice, liberty, and opportunity.
So then, we are seemingly stuck with the rich getting even richer, and even more privileged, because the only entity that can stop such, which is our national government, has effectively been compromised, or even worse, actively aids and augments those superrich; in which, as long as this continues, the less the common man will have, and the more the few will have wrongly taken and wrested away from them.