Well, yes, many of them appear to be. Mostly not as rich as the USA, of course, though, but if wealth was all that mattered then Monaco would be the greatest country on hte planet. And I should remind you also that not all countries in Europe have parliamentary systems anyway. France and Russia don't, for example, and there are also parliamentary democracies outside of Europe, like Canada and Australia.

The only one that seems to have failed in the same way as the US system has failed is Hungary (Turkey had a broadly similar systemic failure, but isn't a parliamentary republic). Now, obviously, a parliamentary democracy isn't a _guarantee_ that you won't fall into autocracy/kleptocracy (notably, the Weimar Republic was one, albeit a poorly designed one), but they do seem more resistant to it than presidential republics, where it seems to almost happen more often than not.