We don't know for certain that he can't use the Mangekyou Sharingan. There must be various ways of obtaining it unless you are going to say that Sasuke can't obtain it without killing Naruto. It seems to me that the restrictions of Kakashi not being able to fully utilize the Sharingan have given way to him being able to fully utilize it but at a greater Chakra cost than an actual Uchiha.Originally Posted by DarthEnder