actually, we know: “vgam es hagoy asher ya’avducha, dan anochi” (i’m not near a chumash, but i think that’s correct). when Hashem tells avraham about galus mitzrayim, which was horrible torture and yes, it was from G-d and we needed it, He also says right there and then that the nation who does it WILL be punished.
yes, Hashem decides at times that we need to be punished, and leaves us “open” to our enemies. but who said the nazis/mitzriyim/yivanim/etc. are the ones who have to do it?
so, while situation is RIGHT as is anything that happens in our G-d run world, the perpetrators are EVIL and yes are punished.