"Dirty Day" is the ninth track on U2's 1993 album, Zooropa. It was co-written by Bono and The Edge.
It originates from the band recording "live" jam performances in the studio during the Zooropa sessions on the band's break in the Zoo TV Tour. The song was written about a character who leaves his family and returns years later to meet the son he abandoned. Many of the lyrics are taken from phrases that Bono's…
I don't know you
You don't know the half of it
I had a starring role
I was the bad guy who walked out