It was right for the Uchiha to become basically extinct? They were the probable cause in most of the World issues involving conflict. After all, you do bad or was associated with bad, you're dead in Sasuke World. I mean look at how Sasuke was affected by his parents being slaughtered, and how much of a toll it took on him psychologically. So planning to murder people that was associated with the darkness of the past won't create mentally unhinged children such as his self? Is this Sasuke's logic? Funny, Itachi murdered the whole clan on that principle, and look at how mentally unstable Sasuke was from it. Itachi later admitted that he may have been wrong for slaughtering the clan, and If he had faith in Sasuke, he may have been the light to stowe the Uchiha away from darkness.