Danzou is actually Kakashi from the future. He has come back using a variation of a summoning technique (which is entirely possible, he knows 1,000 techniques at least. Its plausable to assume there is a time-altering technique somewhere in there.) because something has gone horribly wrong and he needs to fix it by keeping Naruto in the village and protecting him for reasons unknown.

His left side is completely screwed up after a fight that occurred in the future, before he came back. Whatever happened to him twisted his view on 'protecting his friends' and turned him into Danzou as we seem him today: someone who would do damn near anything, no matter how underhanded, to defend the village.

I made more sense than this entire thread.