Quick Question: Why is Kakashi the 6th Hokage? ***spoiler***
I was having a conversation with one of my best buds about Naruto Shippuden, the current fillers and a few bits and pieces of The Last: Naruto the Movie (he already knows that Naruto is the 7th Hokage). He brought up a very pertinent question: why wasn't Naruto named Hokage after the end of the 4th Great Ninja War?
But in The Last: Naruto the Movie Kakashi is the one who becomes the 6th Hokage during the 10 years gap between the end of the 4th GNW and the end when Naruto is named the 7th Hokage.
At that point Naruto is arguably the greatest ninja in the world as the movie shows that's he's an international star, so what was the reasoning behind the council nominating Kakashi for the position of Hokage?
My first theory (and it makes sense) is that being over 18 is one of the minimum requirements to become Hokage (based on Hashirama, his brother, Hiruzen and Minato). You could argue that Gaara was named the Kage of the Sand Village but maybe the rules are different there.
What I'm asking is: Was there any reason given in the manga or animated series as to why Naruto wasn't named Hokage after the 4th Great Ninja War?