There is evil, and then there's organized evil. This is a memorial outside the village where my brother lives in the south of France. It is a typical village, quite small, perhaps a few hundred residents. The memorial commemorates three young French civilians who were taken out and shot by Nazi soldiers, either for "crimes" of resistance or perhaps as a "lesson" to the restive civilian populace.
The German soldiers who pulled the triggers were of course "just following orders."
Evil must be resisted, corralled, vanquished. Interestingly, people don't need to be forced by a central authority to resist evil, though their efforts will prove more successful if they band together and submit to a competent authority of their own choosing. This is the basis of the "good war" or "just war."