(mc)which economic policy was used to american industry during the second industrial revolution?

Economic policy used in the US during the second industrial revolution was the model of laissez-faire capitalism. Socialism and populism have not been used often in the US. The main consequence of the use of holding was to reduce the power of couplings, since it is configured symbolic monopoly.

less available tax revenue

this basically means that when they get money from taxes wirth having a lower gdp they get less then what others have with a higher gdp