It has done a horrible job of it all things considered. Basically all the fabled checks and balances have turned out to be based on nothing but good faith. The founders refused to consider that partisanship would evolve at all, let alone to the extremes it has turned into today.

Lots of other Western democracies are doing a lot better job at it, not least because they have been allowed to evolve and change with the times, while the core of the US political system has petrified in all its archaism.