The problem comes in with

All of the threats that Kyle encountered was in response to the fact that he was playing Timmy Toughguy and actively strolling around with a gun...

Perhaps this may surprise you, but you are not legally justified in trying to kill someone just because they have a gun. Also not allowed to kill someone who has just legally defended themselves in a deadly force encounter, that is for the court system to decide. It is legal to get involved in third party encounters, however you best be sure you're not helping the side that will later be declared the aggressor in court and so it is generally seen as very risky to do.

If at any point he ran - and kept running, or dropped the gun and ran, fully retreating from the crowd I doubt he would have been chased too far and the need to shoot would have been eliminated

Ok at this point it may behoove you to actually look at at least the videos of the incident if not the whole trial which was streamed. He did run. He walked by a car, Rosenbaum popped out screaming "I'm going to kill you," Kyle runs, chase ensues, Kyle gets cornered and turns around to find Rosenbaum reaching for the gun, Kyle shoots Rosenbaum 4x, makes a phone call, the crowd yells "he just shot that dude, get him," Kyle starts running again, unknown man hits him with a rock in the back of the head which downs Kyle, Kyle rolls over and misses Jump Kick Man, then another dude walks up but surrenders when Kyle points his rifle (but didn't fire), then Huber hits him with a skateboard and gets shot attempting to take Kyle's rifle, then Grosskreutz feigns surrender and pulls out a gun he wasn't legally allowed to own pointing it at Kyle, Kyle shoots, Gabe backs off, Kyle gets up and goes to the line of police cars right up the road who give him a bottle of water and tell him to go home, he turns himself in the next day.

Again, you can't "disarm someone" who is legally carrying a gun, that is illegal to do and constitutes a deadly threat, and if he shoots you for trying he will get off.

But he didn't retreat as he was being threatened -

But he did, at every opportunity and by all definitions he retreated until he was cornered and then again until he was downed by a rock to the back of his head.

"The aggressor" isn't whoever you decide, it's the guy screaming "I'm going to fucking kill you" while chasing you through a parking lot.

No one could watch the videos and come away with this take you've constructed. He obviously is retreating in both videos. And carrying a gun in the open is not a provocation to violence. Not is it illegal in Wisconsin.

I hope that, rather than knee-jerk down vote, people will go watch both videos. We can do better than shitheads on the Donald.

Kyle wasn't the only person there with a rifle.

Also if you're not familiar with what happened that night, why are you commenting? Everybody makes assumptions based on the outcome of the incident, but nobody seems to have watched the videos which paint things differently and more clearly.

If everyone would shut the fuck up about this incident there wouldn't be so much misinformation around it, and better yet we'd stop seeing this fuckface in the news.

If you're not familiar, why don't you inform yourself? There's plenty of video footage of the night. There's plenty of witness testimony. We all hate Kyle, myself included, but it doesn't help to go around spreading misinformation. It makes our side look like imbeciles living up to the memes.