Board Thread:Naruto Discussions/@comment-31278419-20170217002708/@comment-26403664-20170217034828

I think the plan was for the Uchiha to completely sneak attack the village by releasing the ninetales; I'm pretty sure Fugaku didn't consider his son to spy on the clan at all. If they controlled the ninetales and successfully did assassinations along with help from outside the village, ie any other hiden village I think it would have turned successful if not crippling Konoha to be destroyed by another source.