"Won't Get Fooled Again" (The Who)

I first heard “Won’t Get Fooled Again” on a hot summer day in the early 80s.  We had our windows open (we didn't get air conditioning until I was a senior in high school), and my mother was tired of hearing our neighbors down the valley blasting Styx or Boston or whatever crap it was.  So she grabbed Who’s Next (1971) and played it at full volume.
“That should shut ‘em up,” I remember her saying.
It was a helluva ride for me: Keith Moon’s drums and John Entwistle’s bass sounding like they were going to blow our front door off, Roger Daltrey’s screams shaking the plates in the kitchen cupboards, and Pete Townshend’s windmill power chords erupting like molten lava out of the speakers.  
When its 43 minutes of classic rock perfection had wrapped, it had shut the neighbors up, alright, and it had made a fan out of me.
The album, which started out as an ambitious followup to the rock opera Tommy (1969), was originally intended to be a new opera called Lifehouse.  Its story centered around a dystopian future where environmental pollution makes it impossible for anyone to travel or do anything for themselves.  Therefore, everyone gets their sustenance, entertainment, rest, etc. through their “Lifesuits,” which are plugged into The Grid—which is creepily like the Internet.  (All of this coming from the mind of Townshend in 1970.)
Townshend envisioned Lifehouse as a totally immersive, completely interactive musical experience when performed live.  Audience members would be invited onstage, hook themselves up to a computer that would gather their vitals, and then listen back as their biorhythms were used to generate unique music via synthesizers, creating a kind of musical nirvana.  Or so Townshend had hoped.
Suffice to say, things didn’t quite work the way he’d envisioned.  Test audiences and his bandmates didn’t really get the concept, and the project nearly drove Townshend to a breakdown.  Only a few elements were retained for Who’s Next, with “Won’t Get Fooled Again” being a key track.
The centerpiece of the song is that pulsing organ line, which builds and retreats throughout.  As Townshend explains in the 1999 documentary Classic Albums: Who’s Next, he discovered the sound by taking the output of a Lowrey organ and feeding it through a primitive EMS VCS3 synthesizer using a “sample and hold” filter, which created a pulsing, oscillating effect, turning his simple block chords into something almost Baroque.  If you watch the linked clip, you'll hear producer Glyn Johns state that, whereas most other rock musicians had only used synths as window dressing up to that point, here the synth line becomes the basis of the rhythm track itself, driving the rhythm at a frenetic pace. 
(As a side note: On Townshend’s own demo of the song, the organ has a more syncopated—almost ska-like—feel because he’s playing the tune at half the tempo.  In fact, the demo almost sounds like a distant cousin of The Band's "Up On Cripple Creek."  Take a listen, and see if you hear the Levon Helm and Garth Hudson influence, too.) 
Often, people assume that “Won’t Get Fooled Again” is about picking a fight with the establishment.  It’s not hard to interpret Daltrey’s scream in the song’s final minute as a piece of burning rag, sticking out of a Mason jar of gasoline.
However, according to Townshend, it’s a call for everyone to stop and think.
“‘Won’t Get Fooled Again’ wasn’t a defiant statement; it was a plea,” states Townshend in the aforementioned documentary.  “Please don’t feel that, because you’ve come to this concert, because you’ve come to this place, that you’ve got an answer.  Please don’t make me on the stage the ‘new boss.’  Cause I’m just the same as the guy who was up here before.  You’re in charge.”
To put it another way, revolution has consequences, and they might be consequences that you didn’t foresee when you were pumping your fist in the air, ten minutes or ten years ago.
A powerful, powerful song from a true genius.