In last 50 years, USA invaded 59 sovereign states. No. of killing? Do I need to mention? Just consider Hiroshima. Nobody has more bloody record than USA. Add Israel, Ethiopia and such allies, the number will be countless...
What is the point in counting deadbodies? Are we trying to establish that deaths by communists means more than deaths by capitalists or vice versa? That would be childish. A death is a death and even if we just consider the modern world, the language of power was always the same, be it left or right. This discussion was not a discussion of communism vs. capitalism, it was entirely about the Indian lefts in electoral politics. So, why do we confuse?
Just for an info. May be it will be useful to read Prof. Amartya Sen's work where he showed how suppression or economic isolation actually kills far more than what a war does. And in this regard, the so called civilized western world is far ahead considering their treatements towards other third world latin american, asian or african countries. So, there may not be much to say in favour of 'democracy' also.