Do not state governments represent "the public"? And how is devolution of power to the states (and then counties, and then cities) an "experiment"?
Increasingly, no. Using Florida as an example, compare the popular vote spread (52%-47%) to the house seats (60%-40%). https://en.wikipedia.org/wiki/2020_United_States_House_of_Re... This is just one example of how election winners in the US - both local and national - are trending over time to be less representative of the people they, well, represent.
>And how is devolution of power to the states (and then counties, and then cities) an "experiment"?
"experiment" in your quoted text refers to the first sentence in the paragraph you quoted. No need to try and twist the meaning of words by taking them out of context. The whole thing is itself a very common reference to the writings of U.S. Supreme Court Justice Louis Brandeis in New State Ice Co. v. Liebmann to describe how "a single courageous State may, if its citizens choose, serve as a laboratory; and try novel social and economic experiments without risk to the rest of the country."
If that isn't convincing, here is George Washington, January 9, 1790: "The establishment of our new Government seemed to be the last great experiment for promoting human happiness."
[1] https://www.historians.org/teaching-and-learning/teaching-re...