Historically, far left governments have killed as many people as far right ones, despite their proclaimed love of human rights. Pretty much any closed, ironclad ideology seems to be capable of ending in mass murder.
So you've made a mistake associating leftist ideology with authoritarianism. There is both authoritarian leftist ideology and non-authoritarian leftist ideology.
And then there's Ho Chi Minh of Vietnam. Their country was occupied by the French and later invaded by and viciously attacked by the United States. So they were communist and perhaps emphasized violent revolution, but how else could you gain your freedom from an occupying army?
But for a modern, United States-centric anti-authoritarian anarchist communist ideology, look up Communalism by Murray Bookchin. Bookchin was critical of Bernie Sanders in vermont as being too centrist.
https://en.wikipedia.org/wiki/Communalism
https://www.youtube.com/results?search_query=murray+bookchin