Killing the uchiha is for konaha? It was his and the elders decision and most likley tobi harvesting the seeds of revolution with shisui to get the uchiha going.
Danzou clearly wanted SG to increase his strength as a shinobi. He preaches sacrifice yet he isnt the one doing the sacrificing. He suffered delusions of grandeur believing he can sacrifice anyone to help him save the world.
look. the whole bullshit start after madara's revolt and the second effort to restore relationship with uchiha by giving them jobs as cops. which also put them under surveillance. and the relationship gotten sour. and the kyuubi attack solidify everything. Uchihas being relocated and itachi playing spy. Shisui is send to keep Itachi in check.
Now where's Shisui fit into this? As the mastermind? Or someone to be nice to Itachi and at the same time using his jutsu to keep him under control?
Danzou actually never spoke a word till sasuke brought it up. Danzou was silent about the whole thing.
And itachi showing up in konaha after hizurens death was to show danzou hes still alive so if he harms sasuke, its his ass.
Also, theres no evidence to show danzou himself planned the entire massacre. I find it more likely tobi has been sneaking in and out of konaha before the 4ths death to encourage revolution. (notice when the kyuubi attacks itachi mentions his parents going out then)http://www.mangareader.net/93-55464-...apter-502.html
And I couldnt see any uchiha helping to fight the kyuubi so its possible they were planning a cou back then with tobi. We will find out soon probably.
And you know why Danzo keep himself quiet? Because Itachi still alive. Ultimately Itachi holds the card, the village top secret is in his head.
Danzo issues the order of the genocide. The Uchiha is revolting and he knew. The third and his counsel knew. The third wants to nego but danzo issues the order to kill. There is no outside force or whatever. Danzo hates negotiation with words. His negotiation is with a blade on your neck. Either you say yes or no.