John Lennon, "Happy Xmas (War Is Over)"
Also produced by Phil Spector, this 1971 tune is as much an anti-Vietnam War song than a Christmas song. John Lennon and Yoko Ono took out billboards across America declaring "WAR IS OVER! (If You Want It)." In the past 40 years it's become a holiday classic, even if the original message sometimes gets lost.