There are two basic issues at work here, what is legal to do, and what is prudent (smart) to do. They are not the same in every case, and clearly not, in this case.
You have a right to carry a gun, and a right to defend yourself, no matter what "potential jurors" might think. Now, whether or not its a good idea in a given situation is a DIFFERENT matter.
IF, by your own actions (or lack of action) you put yourself in (avoidable) harm's way, then both your legal and prudent options become severely narrowed.
And the race card (which will be played by someone if not many) further complicates the issue.
Another complicating factor will be the exact language of the applicable laws. There is a judgment principle that says that one's actions should only be judged by what the actor knew (or believed to be true) at the time. Generally this is a good idea, but there are variations, and if the language of the law says, "knew or should have known", then broader standards can be applied.
I believe a lot of this case will involve why he was there, as much as what he did while there, and why he didn't leave after the confrontation. Because the reasons and facts play a part in others deciding if his actions were reasonable & prudent.
IN simple terms, a "journalist" covers a rally, he's an obvious outsider, an angry mob closes in, he brandishes a firearm, they back off, he puts the gun away. No one got shot.
Based on just that, he did a minor foul the way he brandished the weapon (pointing at people), but no major crime that I see, UNDER THE CIRCUMSTANCES he believed existed.
People aren't going to look at just that, however. And it is those other things that will make some of them want him pilloried, not just punished.
In the Zimmerman case, a lot of the press focus was on if he should have been there, was he right to be there, and do what he did up to the point of the confrontation. Now, this DOES matter, but does it matter as much, or more than what actually happens during the confrontation? Possibly, but not automatically. In that case, from my distant observer's point of view, the press (and prosecutor) decided he shouldn't have been there, and done what it he did, so everything that followed was his fault. The jury looked at the simple matter of "are you justified shooting someone who is pounding your head into the sidewalk?" and they didn't convict Zimmerman for that.
In this case, there was no shooting (fortunately), so all the "harm" done is in the minds of the people who felt threatened, and in whatever violation(s) of law occurred because of the manner in which things happened.
Consider this, if the same situation had happened in a different setting, meaning a group of people "threaten" an individual, who then produces a firearm (and does not fire it) and the threat retreats, if that happened in the mall parking lot, a city park, or some other public place, do you think it would get the same level of scrutiny?
Videos do show what happened, but they usually don't show the entire context, and context does matter. Remember the Rodney King riots?
Now replace the unarmed truckdriver pulled from his cab and severely beaten with an armed blogger (reporter??), who didn't get beaten possibly because he displayed a firearm.
The difference between an emotionally charged rally and an angry mob ready to do violence can be a single thing in literally a few heartbeats of time.
No, I'm NOT condoning his actions, I think he was a fool. I just don't think he should be automatically sent to the frying post, for being a fool when no one was physically injured.
Sorry for the rant, these things get away from me sometimes.