I think Est and the critics are both right. The "victim" was being an idiot. At least it looks that way. But so was the cop. Part of the job of a cop is to de-escalate situations like that. It's irresponsible to provoke a confrontation - for BOTH of them. I know this cop has a history of going overboard, and I bet this isn't that "victim's" first run-in either.
What the tape doesn't show what happened before that started this. Was the cop asking for everyone's ID? Was it just the Muslim guy? I couldn't find that info. Knowing LA police, it's entirely possible that they were acting completely irresponsibly prior to the start of the tape, and if that's true (which I don't know), then it's understandable and applaudable to stand up to it. But if the cop was quietly asking for everyone's ID, because that's the policy, then the victim was just being an idiot, and if he had a problem, he should take it up with whoever makes the policy, not with the cop, who was just doing his job.
But from what I can tell from the tape, it seems neither side has much to be proud of.