Actually, those interred lost most of thier property and businesses as a result, so the interrment did result in economic losses and loss of businesses for the americans citizens who were forcibly relocated to these prison camps. It is important to note that we didn't round up every german american and put them in a camp either. Heres a link that talks about the economic damage the Japanese americans suffered: http://aasreadingoutline.blogspot.com/2008/12/property-los.html
And yes looking back it was the wrong policy but did they know that at the time ? If you lived then can you say for sure that you would have spoken out ?