Okay, feel free to accord Marxists "human rights" while they slaughter you. I'm speaking from experience. What about you?
There are many ways to stop people from slaughtering you, some of which include ways to do so by NOT slaughtering them when they're at your mercy. There are places called "prisons." There is a thing called "due process."
You seem to have a difficult time understanding the concept that would should elevate ourselves above the behaviors of our enemies and not sink to them. If we show the same contempt for life as communist regimes have shown, then we might as well be communists. We'd be no different.
Luckily, we have always shown a higher regard for life, and human rights and general than our enemies have. My mother worked at Camp Carson (later Fort Carson) Army Base in WWII, where we held German POW's. Did we treat captive Germans and Japanese prisoners as they treated their captives? Of course not. Had we, we'd have been no better.