“The real class divide is not between the upper class and the upper middle class: it is between the upper middle class and everyone else.”
The reality of income and wealth statistics say otherwise.
And for political power, the permanent part of the 2017 tax bill raises taxes on most of the upper middle class and greatly lowers it on the 1%, and even more on the 0.1%.
It does seem like that top 20% or so, those with degrees from selective colleges or stable small business ownership, are pulling away from the rest in some ways. But this is just a much smaller phenomenon as the extremely rapid and dramatic increase in income and wealth at the very top.
