History has a funny way of warping reality, which explains the drooling accolades currently being heaped upon the Clash’s London Calling. If you’re going to anoint one album as superior to all others from the Only Band That Matters, start debating whether it’s The Clash or Combat Rock, rather than a record that’s every bit as deeply flawed as Sandinista!.

London Calling has been dissected by every news outlet that matters this past week because it’s 40 years old. The general consensus is that’s it’s the most important record in the long and spiky history of punk rock. That’s right: superior to the Sex Pistols’ Never Mind the Bollocks, Black Flag’s Damaged, D.O.A.’s Hardcore ’81, the Damned’s Damned Damned Damned, the Dead Kennedys’ Fresh Fruit for Rotting Vegetables, and the Ramones’ forever-overrated Ramones.

Pop-culture obsessives have accurately argued that the Clash rewrote the rules of punk rock with London Calling. When Joe Strummer, Mick Jones, Paul Simonon, and Topper Headon first began working on the record in May 1979, the genre had become more about what you couldn’t do than what you could. Punk bands were dogmatically required to be fast, loud, distorted, and stupidly simple, with a strong antisocial, antiauthoritarian, and antibathing streak earning invaluable street-cred points.

London Calling took things in an entirely new direction, drawing on everything from dope-slurred jazz (“Jimmy Jazz”) to Jamaican dub (“The Guns of Brixton”) to Studio One reggae (“Rudie Can’t Fail”) to Stax R&B (“The Right Profile”). Rather than railing on about the Queen’s subhumanry or scraping by on the dole, the quartet dived into Spanish history, American capitalism, nuclear-power paranoia, and the mythology of the bad motherfucker called Stagger Lee.

You want perfection? Start with downbeat anticonsumerism manifesto “Lost in the Supermarket”. Most of us go through life as everyman spectators, standing on the sidelines and accepting we’ll never be movie stars, rock royalty, or sports icons. Strummer speaks for all of us with lyrics like “I wasn’t born so much as I fell out/Nobody seemed to notice me.”

Right from the call-to-arms title track, London Calling is loaded with songs fit for the most thoughtfully curated mix tape. But there’s a maddening thing about the admirably audacious double album. For those listening to it the way that god intended—on vinyl—it’s called Side 4.

There’s a reason that no one ever talks about “Four Horsemen”, “Lover’s Rock”, or “I’m Not Down” as the Clash’s finest moments. It’s because they aren’t.

After three sides where every song is pretty much perfect, it’s like the band was left with nothing in the tank. That might explain the cover of Danny Ray’s “Revolution Rock”. Never heard the original? That’s okay, no one else has either. And admit it, you’ve never cranked the stereo in your vintage Vauxhall to sing along to “You must know a place you can kiss/To make lover’s rock.”

Insanely, the Clash seemed to have “Bankrobber”—one of its greatest and most underrated songs ever—waiting in the wings, but instead we get four throwaways before the admittedly excellent album closer “Train in Vain”. That not even “Train in Vain” (originally written as a throwaway and tacked onto London Calling at the last minute) rescues things speaks volumes.

Which brings us back to the one record that deserves to be hailed as the Clash’s finest moment. For brute power summing up a time that hit Britain like a Molotov cocktail, there’s a strong argument for The Clash (the blue U.S. version, not the inferior green U.K. one). But for sheer ambitiousness and risk-taking, nothing ever reinvented punk rock like Combat Rock.

The 1982 release is the sound of a band that’s officially outgrown a genre that it helped birth. The piano-strafed dance jam “Rock the Casbah” and the stutter-soul workout “Should I Stay or Should I Go” became smash radio hits that endure today. But it’s the druggy sonic experiments—including “Know Your Rights”, “Straight to Hell” and “Ghetto Defendant”—that really make a case that the Clash was indeed the only band that mattered.

Meshing punk with funk, hip-hop, swaggering jungle-boogie, and dreamscape psychedelia, Combat Rock showed Damon Albarn how to reinvent himself with Gorillaz. It blew Kurt Cobain’s mind enough to rank as one of his favourite albums. Without Combat Rock, M.I.A. might never have transitioned from world-music cult hero to platinum-shifting superstar.

Best of all? That one is easy. Combat Rock was originally planned as a double album which ended up being scaled back. Which meant, thank Christ and the ghost of Sid Vicious, there was no Side 4.