360° tour at the Rose Bowl - Pasadena, 25 october 2009
"MLK" is an elegy to Martin Luther King Jr., it is a short, pensive piece with simple lyrics ("Sleep/Sleep tonight/And may your dreams/Be realized/If the thundercloud/Passes rain/So let it rain/Rain down on me"). "MLK" was a part of the main set list for the U2 360° Tour, as the prelude to "Walk On". The band asked fans to bring masks of Aung San Suu Kyi to concerts and wear them during performances of "Walk On" in her support; the song was originally written for Suu Kyi.
(from Wikipedia)
