A couple of points.
The turning point seminal events for the robber baron class were the Santa Clara vs Southern Pacific Railroad Supreme Court case of 1886 that granted Constitutional rights to corporations and the Powell Memo of 1971 that laid out a course of action for the rich and corporations to gain influence and write laws that benefited them solely.
And besides the Kochs and Waltons there are may more robber barons today. If you scratch the surface of any issue of today behind it you will find a billionaire funding it. Social Security. Education. Labor. Taxes. Foreign policy.
What we need to do are four things:
1. Take away the Constitutional rights that corporations enjoy that should only apply to living persons
2. Instate the Tobin Tax
3. Reinstate Glass-Steagall
4. Eliminate the carried interest tax rate that hedge fund managers enjoy and tax the hell out of the troublesome, idle money that funds the pet causes of the rich that are to the detriment of everyone else.