I have stated my opinions on the case in the past.
I am not saying all these thoughts mirror exactly the events on the night Zimmerman shot Martin, but some are still relevant to the opinions I have formed.
If I am in a place where I have permission to be, doing something my neighbors have encouraged me to do on their behalf, then it is not an initiation of force to follow or question someone whom I suspect does not have permission to be there.
There are good ways to approach a suspected trespasser, and there are confrontational ways to approach. Which way is more likely to lead down a dangerous road?
There are also good ways to respond to being approached, and confrontational ways to respond. Which way is smarter?
If someone does approach you due to his suspicion that you are up to no good, it doesn't help anything- and certainly not your position- to get a cocky attitude. Even if the accuser is a cop or other enforcer type (the only "difference" being a false veil of "legitimacy" draped over one and not the other).
A cocky attitude is not a justification to initiate force.
If someone starts hitting you, I would not blame you for shooting that person. Yes, it is self defense even if the other person is "unarmed" (whatever the meaning of that might be to you).
I seriously believe, had I been magically placed into the shoes (or, rather, the skin) of either Martin or Zimmerman right at the instant of "first contact", the result would not have been deadly. But that is only a belief, not a proven fact. However, I have been in situations that could have turned deadly had I not defused the other person. So, there is that...
And please don't forget.