One of David Bowie’s phases was a soul phase, inspired by Philadelphia soul music. America is the home of soul music, of course, so this song makes perfect sense.
In typical self-aware fashion, Bowie described the sound of the album (of the same name, 1975), as “plastic soul”.
In fairness, that is slightly harsh on himself. It’s not cheap, tacky ersatz soul by any means.
The song is definitely a rock song, but when the chorus singers chime in, the level of soulfulness suddenly skyrockets.
On one level, the song is about a newlywed couple who are unsure whether they are in love. On the other, it’s a description of America as he saw it. That means it’s not particularly glowing, describing the political messes of the late 60s and early 70s.
The album has been retrospectively rated highly by critics, because it represents genuinely artistic innovation from Bowie.
The song was rated number 486 on Rolling Stone’s 500 Greatest Songs Of All Time.