Yes, that's what I wrote in my post.
I also wrote about the possibility that Russia secretly sent one in with a team of experts. Which also doesn't make sense. And I also wrote that rebels capturing one (or getting on from Russia) simply would not work out, because of the training, that's required to operate one. It's not Call Of Duty equipment that just works.
While there are several possible scenarios, in the end they differ greatly in plausibility:
- The separatists shot it down because they, lacking the benefit of an air defence network, mistook it for a Ukrainian military aircraft.
- The separatists shot it down knowing it was an airliner because reasons.
- Russia shot it down with their own weapons from behind the Russian border thinking it was a Ukrainian military aircraft because they suck at operating an air defence network (pro tip: they don't)
- Russia shot it down knowingly because reasons.
- Ukraine shot it down because reasons (unless they are complete morons there's no chance they mistook it for something else considering it flew from west to east).
- The US shot it down because they are eeeviiil.
See where am I going with this? Occams Razor: the separatists did it by mistake. It takes the least amounts of assumptions and fits the evidence.
So how did they do it? BUK makes the most sense. Has the range, fits the profile. Where did they get it? Now we're getting into speculation territory but my money is on looted from some half-forgotten Ukrainian depot. So far we still don't have any hard evidence of Russia supplying the seps directly (they like their plausible deniability) but I'm not ruling out that they felt they could deny slipping the seps a BUK. Finally my money is also on it being the TELAR equipped version because you can fire that one without a radar vehicle and it's also the same type as the BUK of which pictures have been spread across social media.
So who operated it? My money is on seps, either self-taught or who Russian instructors had given a crash course and let loose. The reason is that an experienced operator would have deduced that it was an airliner based on its altitude and speed. Trigger-happy sep? Not so much.
Oh, and teaching yourself to operate a Soviet era SAM system - while not exactly easy - can be done.
Case in point.
That's my view of things. As a bonus, it also explains perfectly why the seps are running around like headless chickens and why Russia suddenly took a hands-off approach to the seps and are trying to distance themselves rather than cover things up.