"[1] After the September 11, 2001 attacks, "Peace on Earth" took on additional meaning and consequently was used as an encore song during the band's Elevation Tour, coupled with "Walk On".
"[2] Guitarist the Edge said that "Peace on Earth" came together rather quickly, as he had pre-written the music and then Bono developed his vocal part at the microphone.
[4] The Edge used a DigiTech Whammy effect pedal on the song to create "this bizarre, atmospheric, almost Chinese-sounding" guitar tone.
Co-producer Brian Eno contributed heavily to shaping the song but was absent at the end of the album's recording sessions, having become burned out by the creative process.
On 21 September 2001, U2 performed a few verses of "Peace on Earth" along with "Walk On" in London, England, for the simulcast telethon America: A Tribute to Heroes.
The band performed the song for the first time in over 20 years on 18 February 2024 during their residency U2:UV Achtung Baby Live at Sphere in the Las Vegas Valley, in response to the ongoing Israel–Hamas war.
Irish journalist Niall Stokes calls "Peace on Earth" the band's most "agnostic song yet", saying that it "takes that sense of abandonment" felt in "Wake Up Dead Man" "a stage further".
"[9] Ryan Jones of The Bergen Record felt that "Peace on Earth" contained echoes of the band's 1987 song "Mothers of the Disappeared" in its lyrics and the tone of the instrumental prelude.