Associate
I think what he means is the US was set up as a republic not the democracy it has become.
What specifically is the difference between a republic and democracy to you? Both process constitutions. Separation of powers is common in democratic states as well as republics.
So America should go back to the 18th century with slavery and blacks counting as 3/5 of a person, property qualifications to determine voting rights et al?
18th century America was politically progressive by the standards of its day not now.