Leftist - how can you ignore all the mass murders by large left wing governments such as Cambodia, Russia and China?

The same way regressives ignore the genocide of the Native Americans to build the “land of the free”.

We don't. But they don't represent leftist politics in the US any more than genocidal right wing regimes like the Nazis, Fascist Italy, or Pinochet's Chile are representative of right wing politics in the US.

What do any of those dictatorships/totalitarian regimes have anything to do with leftists here in the US? The most prominent "leftist" I know is Bernie Sanders and he is a democratic socialist.

I could as easily ask right wingers how they could ignore the mass murders by Hitler and the Nazis. They were extreme right wingers, despite the current propaganda tactic of some to identify them as leftists. Hitler murdered all the leftist leaders he could find.

You need to focus, be honest and try to relate your criticisms to the current reality. Fearmongering propaganda doesn't work with sensible people.

Hitler balances all that. Next!

They were so left they became the right, and the right wre forced to be the left!

But doesn't your argument suggest that even the so-called democracies can pull off the same?

All those countries were also led by human males.

How can we ever allow government by human males again? Obviously if they are members of a certain demographic, the nature of the demographic must be the one and only reason for their actions.