Flashback: Simon and Garfunkel's Lost 1970 Song 'Cuba Si, Nixon No'

Simon and Garfunkel didn’t leave a lot of songs in the vault when they broke up in 1970, but that hasn’t stopped Columbia from spending the next 46 years reissuing the duo’s music in every possible sort of package they could think up. That includes too many greatest-hits albums to count easily, along…