It is indeed a nine inch nails song. Johnny Cash never asked for permission, and just released it on his own. Trent Reznor's attorneys wanted to go after Johnny Cash for it. Trent Reznor refuse to take any action and commented that it was one of his greatest honors to have one of his idols use his song. Both sung are great and to me both carry a great but different message.
In Trent's version he's singing to his dad, and parts of the song are his father talking to him as a child. It's a very cold song.
I was listening to this when I was writing my post about Johnny Cash version. Still dont care for it. Though I admit its poweful in a different way. I dont identify with injected drugs. But the music was appropriate and impactful. I actually like Nine Inch Nails for the most part.
