U2's lyrics are known for their social and political themes, and are often embellished with Christian and spiritual imagery. Songs such as "Sunday Bloody Sunday", "Silver and Gold", and "Mothers of the Disappeared" were motivated by current events of the time. The first was written about the Troubles in Northern Ireland, while the last was a tribute to COMADRES, the women whose children were killed or forcibly disappeared at the hands of the Salvadoran government during the country's civil war. The song "Running to Stand Still" from "The Joshua Tree" was inspired by the heroin addiction that was sweeping through Dublin—the lyric "I see seven towers, but I only see one way out" references the Ballymun Towers of Dublin's Northside and the imagery throughout the song personifies the struggles of addiction.