Antioch: So the US is at war with Russia AND Germany. And for what? The reserve dollar hegemony.
The idea that reserve currency status is behind US being the biggest economy is a myth. In 1896, when the pound was the world reserve currency, the US economy was not just the largest - it was 2x the size of #2, the UK. The flow of immigrants was certainly in one direction, from Europe to the US. Even back then, almost 50 years before the dollar became the world reserve currency, the US was the major industrial power.
That was an era in which the UK's British Steel and Germany's Krupp could be said to be peers with their US megacorp counterparts. Today, US megacorps dwarf their overseas counterparts. Foreigners don't use US goods and services because of the dollar's reserve currency status. They do it because US products have been, for over a century, either the best or very close to the best combination of price and features.