Did the Nets break the Celtics? Or did they break themselves?

The decision, according to the official line coming out of Boston, was not spur of the moment, not driven (solely) by the Nets “gentleman’s sweep” last night. Of course, that has to true. Teams don’t move that quickly. There are contracts to negotiate, key players on and off the court to inform, etc.

But ... Danny Ainge’s retirement and the elevation of Brad Stevens to President of Basketball Operations suggest that while the Nets may not have “won” the 2013 trade that reshaped both franchises, the Celtics sure seem to have “lost” it. With all their assets, acquired in that trade and others, the Celtics couldn’t get over the hump. They got to the Eastern Conference Finals three times in the eight years since the trade but never advanced. Three times, including last night, they lost in the first round. That was not the plan.

Moreover, despite all the promise, the Celtics kept losing players for nothing. They used the last of the four Nets first rounders to pry Kyrie Irving from Cleveland only to lose him two years later when he signed in Brooklyn. After a tumultuous three-year tenure in Boston, Gordon Hayward wanted out as well and Boston had to ship him to Charlotte for what was essentially a swap of second rounders. Al Horford and Marcus Morris also left as free agents.

And when Anthony Davis’s father told ESPN in 2019 that he didn’t want his son to play for the Celtics ... if they were to try to acquire him via trade. “I would never want my son to play for Boston after what they done to Isaiah Thomas,” Anthony Davis Sr. said.

Oh yeah, Isaiah Thomas. Remember that?

You can quibble all you want about each individual transaction, slice it up anyway you want, but the reality is that the Celtics never made it to the promised land despite all their advantages. Now, they’re officially in a rebuild or whatever you want to call it.

Yes, they still have two young All-Stars who appear to be happy. Jayson Tatum, 23, and Jaylen Brown, 24, were both acquired as part of the Nets trade. Both are All-Stars and both are great players who could forge a new legacy, depending on other factors.

There are other factors. The Celtics are over the cap, over the luxury tax threshold, with underperforming Kemba Walker owed $74 million over the next two years and a lot of decisions to make. (The Athletic’s Jared Weiss reported Tuesday that the Celtics want to trade Walker, who is 31 and after years of durability, has knee issues. Weiss says Boston would likely have to give up first rounders — plural — to get that done.)

Then, there is the lack of draft picks. As recently as last year, the Celtics had three first rounders and a second. Going forward, they have no extra firsts and a smattering of protected seconds. It’s hard to tell how many of those seconds will actually wind up in Boston. Not a lot.

It’s more than that though. There’s the psychic damage the franchise has suffered. What happened in Boston this week, with fresh accusations of racism — subtle and otherwise — some from within their own locker room; the verbal abuse of Kyrie Irving; the thrown water bottle; and Irving’s punctuation of it all. Some like Brown accused Irving of gamesmanship in making his accusation. If so, it worked.

Will the legacy of 17 championships (only one in the last 35 years) overcome all that? Players talk and it should be noted Kyrie wasn’t alone in his commentary about “subtle racism.”

When Kyrie made his claim in a Zoom call with local media, he was encouraged by a disembodied, off-camera voice who interjected, “The whole world knows it.” Irving echoed, “The whole world knows it.” That voice belonged to Kevin Durant.

In the meantime, the Nets have recovered, no excelled beyond any Nets fans’ dream. They are the favorites to win it all as they look ahead to the Bucks. Their “Big Three” is the marquee trio in the NBA. They wanted to play in Brooklyn, demanded it in fact.

So, now almost exactly eight years after Billy King and Danny Ainge shook hands on the trade that brought Kevin Garnett, Paul Pierce and Jason Terry to Brooklyn and (supposedly) sent the Nets future to Boston, who would you rather be? The Celtics or the Nets? Easy call.