Just let me zip up my flame suit...

I don't know why this keeps playing itself out. Those who believe that Mr. Zimmerman started a conflict that ultimately ended Mr. Martin's life would love for us to believe that Mr. Martin was a sweet endearing boy with a bright future. Those on Mr. Zimmerman's side try to say that Mr. Martin was a thug punk looking for loot and blood.
At the end of the day all it does is rile people up and cause disharmony among a divided nation. If just once, just one time we put aside all of this stupid and senseless class divide/culture divide bull shit and pretended like we were real, intelligent human beings we could see that we all bleed red and that facts are all that matter in case that is only decided by law.
When you are put in the position of judging someone based on a set of guidelines, you follow those guidelines. In this case it was the actions of two people and the law that governs the legal aspects of taking a life. The courts tried to do a good job at allowing all of the factual evidence to come into play as they could but lets talk about what didn't matter for a second.
Skittles, Sprite, failed police exams, hoodies, baby pictures, race, weed, scholastic records and the stand your ground law.
What was important? Armed, unarmed, actions, consequences, disparity of force, and reaction.
If you can put aside all of the petty nonsense that made this the spectacle it became than you can come to the conclusion that Mr. Martin and Mr. Zimmerman were two people that had no prior knowledge of each other. That night they crossed paths and ultimately one of them did not survive the encounter. Mr. Zimmerman would not have had knowledge of the contents of Mr. Martin's pockets or his scholastic records or drug use and Mr. Martin would not have known about Mr. Zimmerman's status as a neighborhood watch volunteer or his inability to pursue a career in law enforcement.
Now here is where things actually get tricky, and bravo to the defense for having it shown as such.
You can see this as one whole incident or as two separate incidents. The moment Mr. Zimmerman saw Mr. Martin a timer started. This "shot clock" if you will, began ticking off the seconds of the encounter. When Mr. Zimmerman ceased his pursuit and proceeded back to his vehicle the clock stopped, the first incident was over. When Mr. Martin approached Mr. Zimmerman the clock started again. As the confrontation continued Mr. Martin achieved the upper hand in the scuffle and Mr. Zimmerman reacted to save his own life by using the one tool he was most afraid of loosing possession of.
Like it or not, if you choose to carry a firearm, there is always at least one firearm at your incident. You cannot allow it to be taken, and yes this does make things more dangerous for all involved. We could argue about Mr. Martin's intentions all we want but the fight ended before he was allowed the use of Mr. Zimmerman's firearm and that is the only fact we can allow in the court. If it had been argued that this was one congruent encounter and that the clock never stopped after Mr. Zimmerman ceased his pursuit, you could say that Mr. Zimmerman started the altercation that ended Mr. Martin's life. You still could not argue that Mr. Zimmerman's actions were not in direct result to Mr. Martin's escalation of the incident. If Mr. Martin had not decided to hit Mr. Zimmerman and then repeatedly bounce his head off the concrete there would have been no need for a deadly force reaction. There may be some arguing over how long the reaction took and if Mr. Martin was still on top of Mr. Zimmerman at the time of the shooting or not but at the end of the trial the jury believed that Mr. Zimmerman RE-acted. If the first action was to hurt or destroy the reaction has every right to bring the same amount of intensity. That is ultimately what won the case for Mr. Zimmerman.
The petty bickering over race, culture, upbringing, who wanted blood who was the good guy. None of that matters, it only serves to further destroy relations among people that without a constant news feed would probably be able to look at each other in public without feeling guilt, fear, or anger.