While we can argue all day on which degree of murder Batman committed or which era of comics it evokes or the reality of a human vigilante fighting criminals, at the end of the day, said logic does not extend to Superman. It corrupts the character. Superman has the power to destroy the planet, but refuses to do so, let alone take a life. By making Superman a murderer, it takes away the appeal of the character: the control of the destructive power and impulses within him.
That is not the core appeal of Superman. At all.
On another note, the lack of imagination and basic reasoning ability in this thread...boggles the mind.
Some of you are overthinking things so much that you're missing the forest for the trees.