The French revolutionary government had moderate and radical factions that coexisted peacefully for many years. The terror wasn’t something that happened arbitrarily, it was an escalating conflict between radicals and (mostly) counter-revolutionaries acting in the interests the French burgeroise. During the course of the revolution, the government abolished an extremely oppressive system of feudalism, established universal rights for French citizens, established voting rights that would eventually lead to universal suffrage in France, and abolished slavery in the French colonies. That’s not to say it was all good (terror, wars, economic hardship, etc) but it completely transformed the entire country in a matter of years, from feudalism to a limited form of democracy, which resembles our modern democratic states much more closely than the system that had been created during the American Revolution.

If your take on the French Revolution is ‘they didn’t have a common enemy so they turned on eachother’ then I would say that it’s you who doesn’t know their history very well.