Last time I checked zimmerman wasn't a cop nor did he do anything that needed some sort of special police privalege.
Unfortunately for you , to detain and question someone you really DO need those privileges. Take the incident you cited from your experience , the actual LEOS had the right and said powers , some citizen running up on you wouldn't have had those powers and you wouldn't have to answer their questions. And if they were aggressive you'd be well within your rights to defend yourself.
And as I stated , in the long run the whole " race issue " is secondary , this goes far beyond that to the citizens right to walk where they please peacefully without undue harrasment or interference.
And also as I stated , giving Zimmerman the benefit of the doubt as regards having a conscience , he could have well precipitated a living Hell from which only death can save him.
He may well have ruined his life with a moment of misguided authoritarian " dogooderism" , in which case society loses not just one possibly productive member but TWO.
As an example ( though extreme) od where such conscience driven grief can lead look to the example a couple of years back of the guy who ran over the child in the Ca Delta while drunk on a jetski.
The courts of course did him up brown , and he pled guilty , and the remorse ate him alive until he ate the muzzle of his own shotgun.
So in the end run , this stands a goodly chance of being a tragedy on *both* sides.