I remember a bunch of Americans telling me that America isn't a democracy, and shouldn't score high on those indexes that rank countries... because the USA is actually a republic.
So of course, there's no sense in comparing the US to other countries unless they're also republics. Or if we're talking about economies.
There are federal elections (of a sort) so the country as a whole can be gauged on that. And on that front... not looking so hot, either, but it's not as bad as certain individual states.