Larry Mullen Jr. of U2's songs, helping to evoke military imagery. During the recording of the album "Pop" in 1996, Mullen suffered from severe back problems. Recording was delayed due to surgery. When he left the hospital, he arrived back in the studio to find the rest of the band experimenting more than ever with electronic drum machines, something driven largely by guitarist The Edge's interest in dance and hip-hop music, and, given his weakness after the operation, he relented, allowing The Edge to continue using drum machines, which contributed heavily to the album's electronic feel. Mullen has had tendinitis problems throughout his
Innocence + Experience Tour forced the band to cancel a headlining appearance at KROQ Almost Acoustic Christmas, as well as a week-long residency as the musical guest on "The Tonight Show Starring Jimmy Fallon". Days before the 14 May 2015 tour opener in Vancouver, drummer Larry Mullen, Jr.'s father died in Ireland, putting the status of the show in doubt. Mullen flew home for the funeral and returned to Vancouver in time for the concert. On opening night, during the band's performance of the final song "I Still Haven't Found What I'm Looking For", guitarist the Edge fell off the stage catwalk while playing