If Frieren doesn’t kill the demons, the demons will kill them. The difference between child Hitler and a demon, is that Frieren knows what the demon will do in the future, just like we know what happens when you release a hungry lion in a room full of antalope.

Frieren might be shooting first in the battle, but the demons shot first in the war.

The demons use human sympathy to gain trust and it works. You feel for them, you want to protect them, may even be attracted to them, and give them a chance and that’s their whole stick. They’re just hungry lions that transformed to look like their prey.

Hitler, and the Nazis, had believed that certain groups of people were inferior and a that only a superior race should exist. So what did the rest of the world do? Those that could fight, fought back to survive and protect those that couldn’t.

If we’re going to compare roles; Demon king is Hitler, demons are the Nazi forces, Frieren and her party are the allied forces. In the show Frieren is defeating the remnants of an active terrorist cell following in the footsteps of the demon king/Hitler.

If you try to put Frieren in the Hitler role, it doesnt make sense. She doesn’t go from town to town murdering anything that’s not an elf. She’s not gaining followers to take over the kingdoms.

You could call Frieren racist towards demons; but if a group murdered your entire village, and you watch them do it to countless others over a thousand years, never meeting a “nice” demon, you’d provably learn to shoot first too.