By the way, Hitler was a Nazi (National Socialist German Workers' Party), a leftist.
Hitler was not a leftist. Besides which, you're massively oversimplifying left and right wing, not to mention involving misconceptions on the nature of the two sides. It's not an economic line, it's not a Government intervention/no Government intervention line, or anything like that alone. Fascism is actually pretty centrist, by itself, but embodies a number of right wing principles, such as power and authority, meanwhile rejecting those on the left, such as liberty and equality.
A liberal, such as yourself, myp, embodies both left and right wing principles. Funnily enough, extremes on both sides. Fanatic support of capitalism is a right wing principle, while tolerance and civil liberties are left wing.
Someone that is considered right wing may support lowering taxes, for example, or raising them, for different reasons. While someone considered left wing may be the same.
Left and right wing just isn't that simplistic. And it's not void - though that doesn't mean people must adhere entirely to principles of either.
Communism was supposed to make society a classless utopia too, and you see how that turned out... taking issue with where the blame goes seems like kind of a moot point to me.
Several things:
*Communism is not utopic
*So-called attempts at communism were nothing of the sort
*I am not a communist