By the fall of 1999, when Smashing Pumpkins started wrapping up production on Machina/The Machines of God, the end of the band probably seemed like a foregone conclusion. Even though original drummer Jimmy Chamberlin had rejoined the fold (he was fired in 1996 for a particularly destructive drug habit), bassist D'Arcy Wretzky had tendered her resignation while the band were still recording. (She was eventually replaced by Hole's Melissa Auf der Maur, who appears in all the promo photos for the album.) Enthusiasm for the music within the band was reportedly waning. Billy Corgan was itching to pursue other projects. By the time the album was done, in October 1999, it had become an unintentional memorial for everything Smashing Pumpkins had been and, simultaneously, an exemplar of where alternative rock was at the time.

The sound of Machina/The Machines of God, which turns 16 on Feb. 29 (or 4 years old if you're strict about leap days), was, of course, a reaction to the sound of Adore, the band's 1998 foray into electronic conceptualism. Machina was marketed as a return to form, but that's not quite right. The form they would have naturally been returning to would have been their breakthrough, Mellon Collie and the Infinite Sadness; but that record was a grandiose, mid-90s indie-pop record with arrangements and radio-friendliness that aspired to (and achieved) heights attained by R.E.M. and U2. Machina wasn't a throwback to 1995. It was a summation of some of alternative rock's most compelling tendencies at the turn of the millennium.

In 2000, the still-nascent alternative genre (nascent, at least, as a radio format, and an aisle at Tower Records) was facing something of existential crisis. The grunge bands and California punks that had dominated the '90s had been supplanted by nu-metal bands like Korn and Limp Bizkit; on the other side of the spectrum, acts like Natalie Imbruglia and the Goo Goo Dolls softened alt-rock's edge into something palatable for soft rock radio. Some '90s alternative bands, like Pearl Jam, decided they didn't care about the direction of the genre and proceeded to do whatever they wanted; others, like Radiohead (whose Kid A came out in October of 2000) dismantled every last one of alt-rock's assumptions, from verse-bridge-chorus to guitars-bass-drums.

Smashing Pumpkins, however, embraced the conventions – new and old – and somehow they did so tastefully. The woozy haze of Machina's production and the droning guitars suggest a stronger influence from shoegaze bands like My Bloody Valentine. But elsewhere, deep bass and riffy, downtuned guitars on tracks like "Heavy Metal Music" sound unmistakably of the era – more Deftones than U2. On "Try, Try, Try" and elsewhere, the Pumpkins sound reflective without descending into pure dourness — like a blurrier, more elusive version of what the Goo Goo Dolls had achieved, perhaps. They combine these elements to back some of Corgan's sharpest melody writing, especially on "The Everlasting Gaze" and "Stand Inside Your Love," which could go toe-to-toe with "Bullet With Butterfly Wings." The result is an album that's easy to place in terms of the time of its release but also doesn't sound dated. That Machina ended up being one of the Pumpkins' worst-selling records is less a testament to the strength of the material and more of a sign that, perhaps, audiences felt challenged more by the message than the music.

Smashing Pumpkins have always been perceived largely in terms of Billy Corgan's ego and, on Machina, Corgan elevates himself to the level of a deity. Thirteen years before Kanye West said "I am a God," Corgan sang (on "The Sacred and the Profane") to "send the bored, your restless, the feedback-scarred, devotionless / you're all a part of me now.” As with Kanye, Corgan's ego is part of the band's appeal, a convenient dividing line between those who can't stand his smugness and those who are compelled by his self regard. Also like Kanye, Corgan's expressions of self-regard can be simultaneously fascinating, entertaining and grating. It's not a "likeable" trait, but it feeds off the contradictions and complexities in the music.

Halfway through "Glass and the Ghost Children," the track gives way to a recording of Corgan talking to someone in what sounds like an interview. "I started thinking that everything I operate on is based... on what I believe God was telling me to do," he says. "God could be my intuition... but I always assume, I always assume that the voice I... hear is the voice of God." Corgan does, in some twisted way, believe if he's not God, he's channeling God directly.

But, within the circle of Smashing Pumpkins, Corgan is God. It was only after critics took stock of Machina (some disliked its disorienting drones, others praised the band's regained sense of clarity) that Corgan revealed the album had initially been intended as a two-part concept album that encapsulated the history of the band. The plan had been derailed in equal measure by label objections (after the flop of Adore) and Wretzky's departure. Machina (as Corgan planned it) was supposed to revolve around caricatures of each band member. But, with Wretzky gone, the album naturally came to center on Corgan's own God-complex. It's a tribute to his writing — Corgan is more lucid and poetic here than on any of the Pumpkins' other material — that it somehow comes off as vulnerability rather than self aggrandizing. But the vestigial moments leftover from the concept album, the ones that don't dwell on Corgan, are even more poignant in this light. “This Time” melds his warm vocal and chilly sonics like a late-October day, teetering on the edge of a total chill. "For every chemical, you trade a piece of your soul / With no return and who you think you know / doesn't know you at all," Corgan sings. it's no wonder Corgan felt he couldn't complete his vision without Wretzky.

In retrospect, the last-minute collapse of the band during the making of Machina seems more like a blessing than a curse: it saved the album from becoming a bloated, over-thought concept and allowed the nuance and confusion to settle in. Corgan (who, of course, brought back the Smashing Pumpkins name five years later) says he's planning to release a reissue of the record that includes newly recorded parts, completing the epic he left unfinished 16 years ago. But we should be satisfied with what we have, too — an overlooked album that represents the best of what ‘90s alternative rock strove to be; and one that, in ways subtle rather than drastic, drives it forward.

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