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This song is based on a riff by Jah Wobble, with a sophisticated guitar part by Keith Levine.

Yes, it’s all just major chords, but for something like that to have harmonic power, there needs to be a lot more going on structurally to balance coherence and surprise – which is being done in a gold-plated way here.

The song starts off with a repeated I V in a completely even harmonic tempo - the most simple and cliched two chord sequence imaginable.

The third time round after the I V we get a IV – which could be an anglican hymn.

But the fourth chord upsets expectations! The root of the chord is not even in the diatonic scale - which has been defined exhaustively by the previous three chords!

But wait, the fourth chord now takes us swiftly back to the initial chord in what sounds like a lovely VII I mixolydian cadence.

Reflecting on this – one way of putting it is that during the period when everything sounded obvious and clicheed (Major I V IV), unexpected stuff was going on behind the scenes in that this was actually a I V IV sequence in the Mixolydian Harmonic mode (harmonic mode are mode where V is dominant by fiat for cadential purposes)

From at point on, the mixolydian VII I cadence - that previously seemed to be so coherence - destroying is actually a major source of coherence - cementing the mixolydian mode. This is structurally solid, but it sounds fresh, in part because mixolydian cadences are relatively rare.

This is not the only way of looking at it, and the claim is not that anyone hears this explicitly, but it is one way of looking at what is going on in this song.

(The underlying analytical idea being used here is an assumption of diatonicity)

The value of this way of looking at things can be tested by using it to write variants predicted to have a similar effect, and seeing whether they work or not.