All of the music used in that game is used so perfectly. The game opens to its title screen with an American flag being flown upside down, with Jimi Hendrix shredding out a scratchy, distorted, echo-y, far-off rendition of The Star Spangled Banner on his electric guitar.
Honestly, they should've licensed more music. Could've used Free Bird too.
Here's a list I found of the non-original songs used in Spec Ops: The Line:
01. Jimi Hendrix - Star Spangled Banner
02. Mogwai - R U Still in 2 It
07. Deep Purple - Hush
09. The Black Angels - Bad Vibrations
10. The Black Angels - The First Vietnamese War
14. Giuseppe Verdi - Dies irae
24. Mogwai - Glasgow Mega-Snake
25. Inner Circle - Bad Boys
26. Black Mountain - Stormy High
27. Martha And The Vandellas - Nowhere to Run
30. Björk - Storm
36. Jimi Hendrix - 1983 ... (A Merman I Should Turn To Be)
37. Groove Addicts - Shellshock
38. Methodic Doubt Music - Half The Man
39. Alice In Chains - Rooster