Another devil's definition of a moderate is a person who thinks that Nazi's wish to exterminate Jews has to be treated fairly and can't be simply dismissed out of hand.
There's more than a superficial resemblance between the two situations btw. Look up Holodomor, when Stalin decided he'll try and kill as many ukranians as possible. 7 million dead in 2 winters. Hear him out tho, he just has a different viewpoint.
It helps in the fight against evil if you understand that evil lies to people, and convinces people that they are the victims.