Neither is the naked assertion "We have an existence proof." Especially in the context of a 250-year-old country stacked up against thousands-of-years-old countries.
England has a monarchy going back thousands of years. Meanwhile, I think it remains to be seen if the younger governments failed to learn the right lessons from the US or have learned from the US's mistakes.
We shall see. Probably on the next quarter century, given how precarious the political situation is in the US right now.