Question about "Walk the Line" movie scene


In the scene where Johnny Cash is rehearsing with his band on the road, all the band members are drunk. June Carter walks in and they give her a hard time. She throws a few beer bottles at them and yells at them. As she is leaving, Johnny yells back at her, "This isn't about a tour! This isn't about a song!"

After he said that I asked myself, "Well then, what IS it about?" Life, maybe?

Any help will be greatly appreciated!


The Adventure Starts Here!
He was drunk. I doubt he really had an answer to his own question in his mind. He was just trying to yell a witty comeback line to have the last word.