And FWIW, there are (by most measures) no other democracies out there which have gone as long under peaceful rule of law as the US. Every other democracy (save by some measures the UK) has fallen to coup or revolution in less than this duration.
Their latest constitutions may work to keep them stable as long as the US has managed. Or they may not. Time will tell.
The real outlier in the US is gun rights.
Are you taking the end of the US civil war as the starting point? If so, then Switzerland has a longer duration of peaceful rule of law.
Even if you do count from the end of the civil war, I would not consider my central thesis destroyed by the small and frankly uniquely weird country of Switzerland. Switzerland is a country that has done very well for its people, but the lessons which have kept it stable and safe over the past two centuries (have a lot of mountains, and don't be worth invading) are not ones which extrapolate out.
And let's be honest -- Switzerland was not functionally independent in WWII. It wasn't necessary to invade, because they did whatever the Third Reich wanted with their stolen gold and borders. This is not the stability I am looking for.
Would you say that Jean-Jacques Rousseau’s political thought has been valuable and influential in the world?
What exactly is your central thesis? It sounds like you're presenting an argument of American exceptionalism, but perhaps I'm misunderstanding your point here.
It has aged well only if you ignore the fact that millions of Americans who were at first considered property, and then “freed” only to be incarcerated and discriminated against, don’t have a say in what “well” means.
Politicians of today understand today’s problems and are better equipped to find answers to those problems. They are armed with a team of educated aides and have access to political science research. I’m confident they could devise a better, modern constitution today.
Are there better people, today, who could lead the country? Of course. Will they ever actually be elected to do so? Sadly, no.
America in the late 1700s was a weird moment in history where educated, forward-thinking intellectuals (not nobility, not just the moneyed elite — actually a lot of men who (mostly) deserved to be called intellectual) actually had a chance to make the rules. They made pretty good ones. Some flawed rules, but good ones.
We're not going to get that again. The real-time feedback of TwitterDemocracy would prevent us from ever getting a document as general yet meaningful as the Bill of Rights, with basically unfettered rights to speech and assembly.
So until I see a viable path to put people in charge who actually surpass them in wisdom and foresight, I'm going to stick to what they put forward. It has aged and worked amazingly well, and have 0 confidence that the politicians of today, if starting from scratch, would do better.