“So What?” was the Japanese-edition bonus track of Metallica's Metallica, known as The Black Album.
Metallica recorded the song as a cover of the Anti-Nowhere League's 1981 punk song. On the Japanese edition, it appeared as track 13 after the album's standard 12-song sequence.
The track also appeared as a B-side to the “Sad but True” single and later became part of Metallica's Garage Inc. collection. Its inclusion connected the band to the punk influences that had shaped its early identity.
The song is not part of the original standard 12-track running order in most editions. That is why questions about the album's track count usually distinguish the standard release from regional editions and later expanded packages.