The Celtics have been in a rut since the trade deadline, and Danny Ainge is pretty obviously to blame. Trading Kendrick Perkins for Jeff Green seemed dumb at the time, and it doesn't look any better now. Listening to the most recent B.S. Report (with Sean Grande, who does radio play-by-play for the Celtics), their discussion seemed eerily reminiscent of the argument surrounding the Billups/Iverson trade. After a closer look, there are some obvious parallels between the two moves.

1. This was a move by a contender attempting to put themselves over the top, while gaining cap flexibility at the same time (or future flexibility, in Boston's case). Grande basically spent the whole podcast rationalizing the decision (Perkins wasn't worth paying, Perkins is injury prone, Perkins only played 18 mpg in the '08 finals, etc.), and Pistons fans and media members did the same thing for Chauncey (He quit in the playoffs, he's not worth his contract, Stuckey is the future, He can really stroke it, but he isn't long and smooth, etc.).
2. GM man-crushes were involved in both scenarios. Dumars had coveted Iverson for a long time and was one Matt Geiger veto short of getting him a few years earlier. Ainge had actually drafted Jeff Green, but was forced to give him up to get Ray Allen.
3. Both GMs clearly traded the wrong guy. Billups and Perkins had a large influence on their teammates, and on one key player in particular (Billups/Hamilton and Perkins/Rondo). Both teams were devastated by the deal. Rondo hasn't been the same since the trade, and there were a lot of tears involved. Rip still hasn't stopped pouting about JOD trading Chauncey, and the team stopped playing for Iverson. Furthermore, the absence of both players fundamentally altered their effectiveness on one specific end of the floor -- Detroit's offense stagnated without Billups, and Boston's defense hasn't been the same without Perk.
4. Green and Iverson both have/had inflated reputations. Iverson was a high-usage volume scorer who couldn't play defense or run an offense (although, to be fair, his '07-'08 season was pretty damn good.). Jeff Green's reputation has basically been built by osmosis. He was a starting member of the up-and-coming Thunder's young core, so naturally he must've had SOMETHING to do with their success, right? Well, not really. His numbers are pretty much the definition of average, and despite the confusing rationalization that he was acquired to guard LeBron and Melo, he doesn't play much D, either.
5. Both Dumars and Ainge were a part of teams that kept their core together too long and suffered for years afterward as a result. The Pistons were aging at the time, and the C's definitely are now. Nevermind the fact that Perkins was the 2nd youngest member of the Celtics' starting lineup, or that Billups' game was clearly going to age the best of any of the Pistons' starters (and has, unsurprisingly).
6. The Billups trade (alongside the Darko pick) has defined how we view JOD, and the Perkins trade will likely have similar results for Ainge. I think Boston will be in better shape -- Perkins still isn't the kind of impact player Billups was at the time, and Allen/Pierce/Garnett are much better than Rip/Tay/Sheed were -- but they're going to have an incredibly tough time replacing what Perkins brought to the table.

Now, do I think Boston is going to plunge into an abyss of sadness the way we have? Not really. We can really only hope this is a portent of things to come for Ainge. They have plenty of good assets left, and their cap situation is pretty good. I do think they have next to no chance of keeping up with Chicago or Miami in the long run, and the short-term damage this does to Boston could easily outweigh any future gains it grants them (which, really, I don't think is going to be much).