Ok. Think about it for a second. What is one of fascism's defining traits? One person in total and complete control. Did Stalin have total and complete control over the USSR? Yes.
Another defining trait of fascism? A cult of personality. Did Stalin have a cult of personality based around his in the USSR? Absolutely.
what i've just said said might be totally wrong. if it is, feel free to correct me.
this is just a theory.
A GAME THEORY!