I see no amount of evidence will stop you from believing what you want to believe. Proletariat is defined as "the working class." In America, that is about 100 million people. You cannot run a dictatorship governed by a group of 100 million. There is no social science person on the planet that would accept your definition. By your definition, America is a despotic dictatorship, not "of the proletariat" but "of the voting citizens."