Do I have this right regarding “communism has killed millions of people”?

So spring is on the horizon and you know what that means!It means I’ll be seeing my republican family members ALOT more (we do most of our family stuff in the spring/summer)So I’ve been learning about Marxism, communism socialism etc just trying to educate myself, mostly because I want to be more than an armchair Marxist, but also because I’m tired of having one sided arguments, I want to be able to rebut my families talking points regarding Communism and Marx. One of the talking points I’ve been struggling with is “well communism killed millions” Obviously it’s a lot more complicated than that, but “complicated” isn’t a good enough answer.However I think I’ve figured out not only the correct response but the actual truth of the matter, and I was hoping you comrades will tell me if I’m on the nose with this or not.Basically the counter argument I would propose would be “You say communism kills millions, are you sure it’s communism, and not authoritarianism?” This will inevitably be met with “well they’re the same thing” or something along those lines, to which I will reply;“Are they? because there is nothing in communism that inevitably leads to authoritarianism. You see ideologies like fascism produce policy proposals such as “ethnostates”, and these things actually do go down a slippery slope leading to authoritarian regimes. Communism is about putting power into the hands of the masses, completely the opposite of authoritarian. So it can’t be communism that causes authoritarianism. So why were there communist authoritarians you might ask? Well I would think it’s because of violent revolution. Violent revolution creates the ideal situation for an authoritarian to take power. The nation is violently split, there’s counter revolutionaries trying to regain power, the people are traumatized and damaged physically and economically, and the easiest way to regain complete control is to instill a single leader to call the shots, thus leading down a path to authoritarianism.”So yeah maybe I wouldn’t say it exactly like that but the whole gist of my counter argument is basically “violent revolution opens the door to authoritarians, not communism” is this a sound argument? More importantly, is it factual?Thanks comrades via /r/communism https://ift.tt/2TcUwVA