Even with immortality there is still one flaw to Sasuke's plan.

[Sharingan King]

Itachi wasn't a huge common enemy that the world banded together against though. He was just seen as a reviled criminal. Sasuke is trying to get the world to ban against him. You can't do that from the shadows even if you do kill the leaders. After all, even if the people all hate you, if they can't find you to attack you because you are hidden away in the shadows, then they will be forced to move on with their every day lives until someone finds you. If they move on with normal life, the result will be normal conflict between the villages. Thus Sasuke would have solved nothing.

Itachi was an S-ranked international criminal and was hated by Konoha for the mass genocide of one its strongest clans. Yet he wasn't always in public view. He protected Sasuke from Danzo by instilling fear within him. He went to Konoha so that Danzo would know that he is alive.

Sasuke doesn't need to be in public view 24/7. He just needs to periodically remind people that he exists and can anhialate them at any time. Knowing of his power would keep them in constant fear so they would band together for security and there would be peace. He doesn't need to be at constant war with fodder. In any case he can deal with them non-violently (solo glance etc).

 

[Eternal Sage]

He basically proved his point by talking about the shinobi alliance. United against a common enemy

 

[narutoblitz]

Killing the Go-kage and Naruto would be enough, but killing the Bijuu would seal the deal. And yeah with their power and Naruto dead permanently (let's assume Sasuke can seal Ashura's chakra permanently, somehow) then yeah his plan may succeed.

Naruto's plan of love and peace doesn't stand any real chance of working, either...

 

[Ultimateone]

i'm with you on this he is very stupid. the world just fought juubi jins, they will be scared of sasuke but they will def try to kill him. all this would lead to is a war to try and kill him, not peace. not true peace anyways. plus his whole "from the shadows bit" is a little deceptive. he will have to let people know he is a threat for his plan to be affective. thus leading to people trying to always kill him, thus the fighting continues.

 

[V h o]

It's obvious that Sasuke isn't thinking straight. 2-4 chapters ago he claims he wants to destroy the bijuu, reason why he is attacking Naruto, yet now he ends up using what he wants to destroy for immortality.