I researched this some after Trump's executive order, and it is interesting because most people know about the Japanese internment because it was the largest, but we also interned Italians and Germans. These three groups were also prohibited from buying certain items that could potentially be used in sabotage.
My German-born great-grandparents were not molested by the government during WW I, though there was harassment of Germans and German-speakers. And in WW II the US had admirals and generals with names like Nimitz, Eisenhower, Eichelberger, Gerow.