War is hell, Nazi leadership was evil. Imperial Japanese Leadership was evil as was the bushido code as it was used to justify implorable actions. The allies made mistakes in hindsight.
A very small percentage of the German military personnel were Nazis and did evil deeds. As another poster mentioned, the subject tanker did his nation's duty. We shouldn't hold ill will 70 years later. Thank goodness as I have to live with and work alongside Germans and Italians.
Go read The Forgotten Soldier.