Earlier today, I published a post exploring the idea of America exiling its prisoners instead of incarcerating them (specifically to Madagascar). I don't seriously endorse the idea but given the burden our prison system is under, I thought it was interesting to explore. However, I decided that it needs to be thought about more carefully so I unpublished it and saved it for a later date.
In the brief time it was up, a commentator wrote (and I'm paraphrasing because I forgot to copy/paste) that Hitler wanted to send Jews to Madagascar (I think we chose the same island) and he/she hoped I wasn't planning something like that. That doesn't work.
The ethical problem with Hitler's plan was not that he wanted to exile a group from a country. It is that he wanted to treat a group of people differently from everyone else on immaterial grounds (ie, religion). Ignoring the nature of the crime for the moment, treating prisoners differently from non-prisoners is not unethical; we do it everyday when we send them to jail. The Hitler analogy is false.