Pretty much. I don't hold much faith in human rights or their fundamentality. Might makes right, and whoever has the might decides what is right.
As for defending the people, is there really that big of a difference whether a murderer is kept from murdering by being locked up or just killed? And if killed, does it really matter whether it's done in a state-sanctioned execution, or by his own ilk after they've had their way with him? Fact of the matter is, he won't be killing anyone again, which is kind of the whole point of punishing him one way or another.