Hey, I'm in class so i only have a few seconds to answer this.
Violence should only be acceptable (in a form of a violent revolution) if democracy has been disregarded by the original party in power. (for example, if one of an opposed party was voted in using the democratic system and the other part declared absolute power therefore disregarding democracy)
And for your third question: This is basically a question of who is the lesser of two evils, and i can't really say. They were both equally bad, but obvioulsy the larger death tolls lies with Stalin. So, i am urged to say Stalin, but i wont because Hitler was just as bad in his methods.
\"He who controls the past, controls the future. He who controls the present controls the past.\" - 1984
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I\'m gonna change the world one day! Or, maybe i wont, but i\'ll be damned if i dont try. - me..