Not only after WWII, but before. The Nazis made many people flee to the US, e.g. Einstein fled to the US in 1933. For Germany in particular there was a brain dr

Not only after WWII, but before. The Nazis made many people flee to the US, e.g. Einstein fled to the US in 1933. For Germany in particular there was a brain drain (and then mass killing of Jews) that devastated German intelligentsia and we never recovered from, look at Nobel Prize laureates before and after the Nazis, artists before and after the Nazis, and on and on goes the list.