Carolina March has an excellent take on what the UNC-Duke rivalry really means and how in it's purest form it is just a natural impulse for Tar Heel fans. He also does a great job deconstructing the meanings the media has attached to the rivalry over the years in their effort to market it to a larger audience which he rightly points out is not really possible:
So if you're watching the game from outside the Carolina perspective, just know the announcers are lying to you. Not intentionally, they just lie out of ignorance. They map it onto rivalries they do understand, like the Yankees-Red Sox or the various clashes in SEC football. But it doesn't work like that. There's a different feel to it, that can't be described any more than a fish can describe water. These are universities that were trying to eradicate one another since before the sports they compete in were invented. It's not here to be marketed, it's not here as a spectacle, it's something to live and die for in three-hour blocks, bracketed by a Southern politeness filling the spaces in-between. It's Carolina beating Duke, and there are few moments sweeter.
One aspect of the rivarly that makes it completely different from any other is these schools are eight miles apart and they have won between them six of the last 25 national championships played. With full apologies to Alabama-Auburn, Ohio State-Michigan, Texas-Texas A&M, etc, etc, etc. but there is not a rivalry in college sports which boasts two teams within that kind of proximity who also routinely contend for national titles in the same year. The stakes are so high when these two meet, it is bragging rights, conference titles, and it also has an implication on a national scale. And if none of that were true UNC fans would still treat this game like the ultimate battle between good(UNC) and evil(Duke).
It is college basketball's version of Armageddon. And it is now a mere 24 hours away.