he fuked up. all he had to do was take down the main military force of the clan.
with no army, they cant possibly rebel.
you think he cares about killing someone who is trying to start a war?
no one tried to start a war except itahci whne he destroyed the most powerful clan in the world and thus left konoha open to attack
Killing them was best. At that point doing, they wanted to be killed anyway; that's why they had their last words with Itachi and just sat there waiting to die.
prison is best. killing them is psychotic.
Do you have any idea how shattered and absolutely miserable their lives would be if Itachi "spared" them?
do you remember sasukes life was only shattered and miserable once itachi beat him inot a coma?
Sasuke was to be kept in check, if his parents who were leading the coup raised him what could possibly go wrong? You saw the guy he is a complete emotional wreck with his clan.
because of itachis torture and abuse
s. Itachi is struggling to try and keep the blade from plunging into his parents. Something/one is driving him to do it. Reason? Sets up the conditions of Sasuke's loneliness and darkness. Ensure others cannot decipher the Uchiha tablet.
he killed his parents to turn his brother into a supervillain?
think danzo ordered him to kill every single uchiha in existence , everyone but one, sasuke.
If someone was to survive, he could end up being another madara.
then danzo is the one who needs to be kileld for ordering such an atrocity.
if someone were to survive they can easily end up the hero of the village for ending the corruption, as was the intention of the uchiha rebellion.
if your killing people because thye might be evil in the future you might as well exterminate humanity.
Because he was under orders to kill everyone. The only he could save was Sasuke.
he alreayd proved he didnt care about orders when he betrayed and threatened his own superiors with high treason if they dont obey him. hes arrogant and foolish.