Amazing topic.
Kanye West "NIgga Heil Hitler" and "Cousins" are obvious recent ones
Nirvana "Polly"
The Smiths "Suffer Little Children"
Jimi Hendrix "Hey Joe"
Korn "Daddy"
The Rolling Stones "Gimme Shelter"
Bruce Springsteen "Nebraska"
Pearl Jam "Jeremy" (the music video actually scared me when I was a kid)
The Associates "Dates and Numbers"
Geto Boys "Mind of a Lunatic"
Lady Gaga featuring R Kelly "Do What You Want"
Morissey "Jack the Ripper"
Captain Beefheart "Dachau Blues"
Sublime "Date Rape"
Definitely stretching the definition of pop music here but I actually love all of these songs.