It's not necessarily pure, native intelligence at work. America has a risk-tolerant culture and massive internal market, with the world's most-powerful currency and biggest stock market, and an unparalleled venture capital system. That makes it easier to advance and finance novel ideas or niche specialties. People with good ideas tend to move to the USA, so there's a universal brain-drain effect. Only a few regions, such as Bavaria, can even attempt to keep up and retain talent and entrepreneurs. Whoever has the reserve currency ends up being That Country, so if the USD falls, someone else will get passed the Smarty-pants Baton. Or we all just use Bitcoin and can live wherever we want.