If Stalin was able to save the lives of 50 million people who would otherwise have died by killing 10 million of them (which I don't necessarily think is actually the case, but supposing it was), I call that a good act. "initiation of force is bad, period" is not a good moral philosophy.
Yeah, Stalin is a great savior of humanity. Let's give him a Nobel prize for killing only 10 million while he could easily kill everybody. Thank you for showing me the path of enlightened.
