‘Mainstream’ (‘orthodox’) historians mostly agree that both Adolf Hitler and Joseph Stalin created essentially criminal political regimes (systems) that committed horrendous crimes on a daily (if not hourly) basis. Including (but not limited to) horrible crimes against humanity. Which is, of course, true and correct.
However, most (if not practically all) ‘mainstream’ historians share a fundamental opinion that on the Eastern front of World War II a ‘good’ dictator (Stalin) was fighting a ‘bad’ or ‘evil’ dictator (Hitler). In this section I will demonstrate (beyond the reasonable doubt) that it was not exactly the case.