As I argued in my 2011 article on National Wealth and IQ at the Edge: American Exceptionalism, East Asian Mediocrity, the US is surprisingly wealthy for a country for a country of its national IQ, which is respectable but modest by developed country standards.
There are many possible reasons for it, which I listed (e.g. economies of scale, “American alpha” in finance, etc).
One of the strongest ones, and which also apply to Israel and India, is that it has a large smart fraction. Furthermore, this smart fraction gets massively turbocharged every year by aspiring foreign inventors (graph h/t Patrick Collison).
Look at that! Even Germany, which has sucked up something like a quarter of Romania’s doctors, is basically only treading water. So is sunny Australia, with its excellent climate and Anglo culture.
So far as globally minded inventors go, the US has long been the only game in town.
But the US is now destroying itself on account of some crazed leftists exploiting invented minority grievances, and the likely election of Biden – who is less economically progressive than even HRC in 2016 – promises renewed infighting between the neoliberal/centrist Dem elites and socialist insurgents, as conservatives skunk away to the corner. The chaos isn’t going to end any time soon. Will the US still be able to continuing poaching talent from the rest of the world in the state it’s in? I doubt it.