You are right, the internment was a mistake, but still needs to be viewed from the context of the time. I had relatives that were in the camps too, so I always thought I was familiar with the history of the whole thing. It wasn't until a few years ago I learned about the Niihau incident during Pearl Harbor that influenced the decision to use relocation camps. Even more recently, I read that the US had broken the Japanese naval codes and I think identified some spies as well, but they couldn't let them know, or they would change the codes. So, relocating all Japanese in the area kept them from transmitting info without the enemy realizing how much they knew.

In the end, it's still wrong to imprison citizens without cause, especially since many lost homes and businesses, but it's also wrong to simply label it as pure racism as is popular today.