Your arguments in this thread seem to be a bit all over the place, and not entirely cogent with regard to what specifically you are attempting to say. It sounds like in this comment and others further down-thread, that you're suggesting there was not an increase in economic inequality prior to 1920. This is nonsense.
> Prior to 1920 there was basically zero income tax, and it's hard to argue that in the preceding era, especially 1850-1920, inequality was on the rise. Hell, one segment of the population OWNED another segment of the population.
First off, just in your chosen period of 1850-1920, slavery only existed for 15 of those 70 years. I don't think it has anything at all to do with evaluating the state of income inequality in the period--except to have drastically increased its relative levels when the whole of enslaved Americans were made free and joined the ranks of the working masses. What happened after 1865 is an indisputably clear narrative of the newly recognized widening gulf between the wealthy and the masses, elevated to the national stage as a critically important civic conversation. Given the history of the post-Civil-War to pre-WWII era, it is really not difficult at all to argue that inequality was rising--and widely recognize as such. In fact, suggesting that it wasn't is almost laughably ignorant of the period's history.
The increased wealth of pre- and early-industrial capitalists was widely acknowledged at the time to have deleterious effects on social, political, and economic spheres. It was overwhelmingly part of the national dialogue, and fed into the rise of populist movements, social and political agitation, establishment and positive public reception of unions among the working class, political campaigns, local political machinery manipulations, and so much more. The gulf that separated the wealthy from the masses between the Civil War and WWI was a big fucking deal. This inequality of economic conditions, and the resulting power imbalances, along with the ability to purchase and maneuver the state and national forces to protect capitalist interests led to riots in the streets, creation of new political parties, and overwhelmingly massive changes to the social, economic, and political landscape during this period.
I know of no historians of America since 1850-1950 who would, even in jest, suggest income inequality in the late-19th and early-20th century did anything but rise. The only exception to this widely recognized and documented state of affairs occurs after 1918--a notable decrease in the interwar period, a marked plummeting during WWII, a steadying greater equality in the post-war decades, until inequality began rising again in the 1970s. Hell, I'm actually amazed that anyone seriously disputes any of this. It's American history 101--a constant, meandering power struggle between the wealthy and everyone else. This has been a staple of American political, social, and economic life since colonial times. We have, as a nation, had this argument before ... many times.