From the late ’70s into the ’80s, two of the most vibrant strands of American popular music were heartland rock and the American underground. These two traditions were very distinct, and there was no overlap. The former, the more mainstream of the two, was the domain of rock gods like Bruce Springsteen and Tom Petty, as well as acts like Bruce Hornsby. These artists and bands often employed keys and the saxophone, although they were primarily guitar-driven.
The American Underground evolved from the fast, aggressive, stripped-down attack of punk into the no-wave sound of bands like Sonic Youth and the shoegaze of My Bloody Valentine. Distortion was a key feature of their sound, and they tended to eschew large arrangements, often sticking to guitar, bass, and drums.
Formed in Philadelphia in the early ‘oughts by Adam Granduciel and Kurt Vile, The War on Drugs combines these two disparate traditions, with a heavily guitar-based sound that uses lots of distortion.