Proof that post-punk can produce pleasing pop, "Train in Vein" by The Clash is unbelievably catchy. (The Cure pulled the same trick in 1992 with the radio-friendly "Friday I'm in Love").
I'll argue this is the group's best-aged song; it still gets mucho airtime on my road trip playlist.
The melody is perfect and the harmonica is a nice touch. The heartfelt vocals convincingly deliver the heartbreak.