A 220-year history which included being the bad guys in the Greek-Persian War saga. The United States has already lasted longer, grown larger, breathed freer. We did well ignoring them and taking our cue from the Greek city-states who defied them.
(OK, so I just watched the DVD of 300 Spartans a couple weeks ago.)
It is my humble opinion that we took our Republic from the Romans and not the Greek City states. But government schools teach different. All the ancient history I have read would indicate that it was the Republic of Rome that provided our founders with their ideas of a representative Republic, which is what our government is, thank goodness it is not a democracy, or we would not have made it this far.