I pulled this from wikipedia: Perhaps it raises more questions than it answers:
http://en.wikipedia.org/wiki/Johnny_Cash
When invited to perform at the White House for the first time in 1972, President Richard Nixon's office requested that he play "Okie from Muskogee" (a satirical Merle Haggard song about people who despised youthful drug users and war protesters) and "Welfare Cadillac" (a Guy Drake song that derides the integrity of welfare recipients). Cash declined to play either song and instead played a series of more left-leaning, politically charged songs, including "The Ballad of Ira Hayes" (about a brave Native-American World War II veteran who was mistreated upon his return to Arizona), and his own compositions, "What is Truth?" and "Man in Black". Cash claimed that the reasons for denying Nixon's song choices were not knowing them and having fairly short notice to rehearse them, rather than any political reason.[9]

[edit] Highwaymen