He said dictator and communism in the same context, that is incorrect. Communism is a collective, there is no central power.
Communism has always turned into an autocracy one way or another.
But they're not communists, they say they are, but it's just a dictatorship.
And yes, communism is a theory, it hasn't worked in practice, but that doesn't mean it can't.
Communism has never worked, and most likely never will. Also if you paid attention during school you would know that the Korean war was because communist north korea tried to take over south korea, so nonnel saying that was perfectly fine.