Don't call him an idiot when you were the one who was wrong. He said rasengan = the technique, Rasengan (since there'd be no name for the doujutsu yet) = the kekkei genkai.ok, i'm sorry, bu your an idiot
your thinking that rasengan is a doujutsu?? then why can anyone do it? Kakashi can do it, Jiriya can do it, Naruto, Minato, plus others probebaly
I don't really believe he has a doujutsu since there were only 3 in japanese myth as pointed out already, and it'd kind of defeat the purpose of Naruto doing all this on his own as an average shinobi who never gives up. (Excluding the times where he uses the kyuubi's chakra)
I just think it'd be a really bad hit to Naruto if he had a Kekkei Genkai and the kyuubi and still wasn't that great of a ninja, so kishi wouldn't do it. It's pretty much given that Naruto will be the underdog of the story until the very end.