It can't be helped. Everybody has an equal right to live. If you aren't ready to get your own blood spilled, don't be eager to have others' blood spilled. However, I'm just talking about this from the perspective of Itachi's theoretical other choices, instead of the poor one he made. You can't seriously claim that massacring the entire clan was the best and only choice. It's no proper answer at all, it's just an easy way out chosen by a coward.

Naturo has been fighting against those easy, cowardly ways throughout the story, in his own foolish way. Like DE said earlier.