In the dying moments of Game 5 of the 2012 NBA Finals, Russell Westbrook, Kevin Durant, and James Harden stood on the Oklahoma City Thunder sideline, arms around each other, and looked on as the Miami Heat closed out a championship. It seemed, at the time, like they were staring at their future, and the Thunder's. But seven years later, that image, which once symbolized so much possibility, now stands as an emblem of everything that never was.

Who could've imagined the historic assembly of young talent on that sideline disintegrating without ever making it back to that stage? Harden never played another game for Oklahoma City. Durant was gone four years later. The Thunder improbably acquired another superstar (Paul George) to pair with Westbrook a year after Durant's departure, but George just forced his way to the Clippers. Now, Westbrook and the front office are working toward a trade that would ship him out and officially end this era of Thunder basketball.

Its legacy - and Westbrook's, by extension - will be complicated.

Durant, Westbrook, and Harden have all won MVP awards. They've made a combined 23 All-NBA teams, including 12 first-team appearances. It will never stop being insane that they all once played on the same team, and that the Thunder nabbed them all (plus a three-time All-Defensive first-teamer in Serge Ibaka) in three consecutive drafts from 2007-09. We may never see anything like it again. Heck, even George, during his two-year stopover, made two All-NBA teams and an All-Defensive first team, with a third-place MVP finish for good measure.

It's all part of the Thunder's great duality: Few teams this generation have held as much talent in their grasp, yet it's hard to think of another franchise that has ever let as much prime-age talent slip through its fingers in such a short amount of time.

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That 2012 Finals appearance was part of a six-year run of sustained contention in which the Thunder reached at least the conference finals four times. (The two years they fell short, it was because either Durant or Westbrook was injured.) They are, without question, one of the defining teams of the decade.

Other organizations tried in vain to replicate their roster-building model. Only the Spurs have won more games during the 2010s. When the Raptors swung a trade for Kawhi Leonard on an expiring contract last summer, they drew on the Thunder's precedent of having done the same with George - who'd similarly expressed a desire to be traded to an L.A.-based team - and successfully re-signed him.

For all the crucial decisions general manager Sam Presti's front office got right, it also made mistakes, one of which proved catastrophic. The Harden trade - which in sum netted them one middling Kevin Martin season, three underwhelming Jeremy Lamb seasons, and Steven Adams - will live in infamy as one of the most damaging deals in modern NBA history. The alternative will forever be one of the league's burning what-ifs.

The Thunder dealt Harden in part so that owner Clay Bennett could duck the luxury tax, and in part because they already had two ball-dominant stars and didn't envision a future in which all three could peacefully coexist. (The latter point now feels almost inarguable.) They chose Westbrook over Harden, but in a way, they also chose Ibaka, knowing he would be lower maintenance. The decision was questionable at the time and looks exponentially worse in hindsight: The new influx of TV money rendered those tax concerns moot, and Harden morphed into one of the greatest offensive players of all time.

Still, in the years immediately following the trade, the Thunder remained ridiculously good, and their inability to get over the hump had more to do with bad luck and uncontrollable circumstance than it did poor management.

What if the Rockets' Patrick Beverley hadn't crashed into Westbrook's knee and torpedoed their 2013 playoff run, or Ibaka hadn't injured his calf midway through the 2014 conference finals, or Durant hadn't fractured his foot in 2015, or Klay Thompson hadn't ascended to the astral plane in Game 6 of the 2016 West finals?

On a smaller scale, what if Andre Roberson hadn't blown out his knee in the middle of a Defensive Player of the Year campaign in 2018, or George hadn't messed up his shoulder during his MVP push this past season?

When Bennett signed off on a massive luxury-tax bill last summer - the cost of bringing back George and Jerami Grant while continuing to pay top dollar for Westbrook and Adams - it almost felt like an attempt to rectify his previous, tight-fisted missteps. But the Thunder could never get back what they squandered. Smaller missteps that might've otherwise been inconsequential hamstrung the brief Westbrook-George era.

They didn't acquire enough shooting, never managed to adequately build out their depth, and took a gamble on Carmelo Anthony that flopped spectacularly. Two years with George failed to produce even a 50-win season or a playoff series victory. George's final moment in a Thunder uniform was spent watching Damian Lillard's 37-foot series-winning bomb sail over his outstretched arm and drop through the net in Game 5 of the first round. It wasn't the result Bennett thought he was paying for.

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The Thunder might still have succeeded, but Leonard's recruiting pitch to George changed everything. The Clippers offered both the comfort of home and a far more realistic chance of contending for a title. With two years and a player option left on his contract, George asked for a trade, and Presti opportunistically (if reluctantly) pivoted to asset-acquisition mode. The teardown continued when Grant was moved to Denver.

If or when Westbrook becomes the next domino to fall, the Thunder's decade-long run of relevance will have given way to a full-scale rebuild.

Inevitably, the brunt of the blame will be borne by Westbrook. Whatever the extenuating circumstances involved in Durant's and George's decisions, it's impossible to escape the fact two co-stars have opted to leave Westbrook for other teams. The Thunder's playoff struggles in the post-Durant era, and Westbrook's role therein, bring back a familiar tide of judgment and questioning each spring: Is any team Westbrook plays for destined to be swallowed by his unyielding style? Will he ever develop any off-ball utility or become the kind of defender his physical profile suggests he could be? Can he find a more productive way to channel his on-court fury than engaging in petty personal squabbles?

At this point, it may be too late for those questions to matter. Westbrook is still a dynamic, game-changing player in many ways - he just averaged a triple-double for a third straight season - but he's on the wrong side of 30 with his athleticism in decline and his sketchy jump shot looking more broken than ever. He loosened his grip on the Thunder's offense considerably last season to allow George to spread his wings, and it still wasn't enough.

The super-max extension the Thunder gave Westbrook the summer Durant left is an albatross now - four years and nearly $170 million remain - but it was a no-brainer at the time. The small-market franchise had just suffered the most crushing string of defeats imaginable: the one-two punch of losing a 3-1 lead to the 73-win Warriors in the conference finals followed by losing Durant to those same Warriors in free agency. Reeling from the departure of one homegrown star, weighing the necessity and potential fallout of trading another, the front office was approached by Westbrook, who signaled a desire to stay put for the long term. What were they supposed to do?

Westbrook's decision to double down on his commitment to the franchise reflected both his sense of loyalty and his bull-headed self-belief. He finally had a team that would be entirely his. In that first post-Durant season, he kept them relevant, dragged them to the playoffs, and made them worth watching with his incendiary MVP campaign. To be treated just two years later as a cumbersome contract needing to be shed - one that may indeed carry negative trade value - is the final, tragic act of his Thunder arc.

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It's fine if you want to say the Thunder kept the wrong guy when they had the ability to choose, or that Westbrook's limitations and inability to adapt are what ultimately doomed the franchise to its present fate. But it's also important to acknowledge that he is the reason the Thunder's competitive window stayed open this long, and one of the biggest reasons they now have a war chest of assets with which to plot their future.

There is no George trade without Westbrook, and George doesn't agree to re-sign if not for the on- and off-court bond he and Westbrook built. The Thunder could have lost him for nothing. Instead, they traded him for Shai Gilgeous-Alexander, Danilo Gallinari, four unprotected first-round picks, a protected first-rounder, and two first-round pick swaps. Westbrook made that possible.

The rebuild will still be long and painful. Outside of Gilgeous-Alexander, the Thunder don't have much young talent to build with, and the picks coming from the Clippers, Heat, and Nuggets as part of their sell-off are unlikely to land in the lottery for at least the next couple of years. But as bleak as the near-term outlook appears, the Thunder may ultimately come to thank George for forcing their hand and giving them this out.

It allowed them to negotiate a haul they couldn't have possibly extracted under different circumstances. In a few years, they'll be better positioned than they would've been had they kept George and played out the string with first- and second-round exits until his contract expired. They now have an impetus to trade Westbrook, which they otherwise would've had a hard time justifying - both to George and the fan base. They can rebuild in earnest, with a bounty of draft capital, a blue-chip prospect, and (assuming a Westbrook trade gets done) a clean cap sheet moving forward.

For now, though, we're left to sift through the rubble of the Thunder teams of the past decade: all that unfulfilled promise, the would-be empire reduced to Westbrook, with his sneer of cold command that seems to say "Look on my Works, ye Mighty, and despair" while around him the lone and level sands stretch far away.

This Thunder era can be anything you want it to be. A blueprint. A cautionary tale. A parable of small-market possibility, or despair. All of the above. It's been a unique - and uniquely frustrating - run. Now it's ending. Let's pay our respects.