What follows is, so far as I know, new. It is, too, what Dr. McElhone described as intuitively obvious to even the most casual observer. I have expected that one of the mainstream pundits would get around to offering it up real soon. Real soon hasn't happened, so here we go.
What we know so far is that Orange Julius Caesar and his followers are motivated by white paranoia and white grievance. What we don't know is why it works. Certainly the message is 'Make America White Again' before we're no longer the one race majority. This is what appeals to the lower class white folk, whose only solace in their poverty is the certainty that black and brown folk could be treated even more poorly; there is 'an other' identified to be below them on the totem pole of society. But what motivates the Koch cabal? Ain't no black folk coming to take their billions. They don't need such reassurance. What gives with them, and pretenders to their throne?
Well, it seems pretty obvious. Consider how government is run. Citizens pay taxes of various sorts, and government spends such funds on public goods. Now, when income is more or less equal, each citizen pays more or less the same amount into the kitty. A progressive income tax, which we allegedly have, weighs the wealthy more than the poor out of a sense of fairness. No one, or group, has cause to complain. It is shared sacrifice for shared benefit. Prior to the income tax, most Federal revenue was from sin taxes and tariffs, the latter being in effect a national sales tax. Some assert that the income tax (by way of amendment) coinciding with prohibition wasn't a coincidence, rather an offset to revenue source.
Which brings us to now. What we know is that income and wealth continue to concentrate. We need only recall Romney's 47% admission. It turns out that among the 47% are some quite well off citizens. But the effect remains: as income becomes more concentrated, those at the top see little reason to pay taxes for services they expect they'll never need. After all, they've got plenty of money. In order to keep the government running as it has been, requires $X. But with fewer citizens having sufficient income to be subject to the tax, those privileged ones must needs contribute more to meet the $X requirement. And they just don't want to do that. So Orange Julius Caesar lowered their taxes overwhelmingly. In due time, he'll call for raising taxes and cutting benefits on those of the 47% who aren't well off. "The American taxpayer can't afford it!!"
This is the driver for the 'Donor Class' that pushes Orange Julius Caesar and Trumpism: revenge of the privileged class.