BTW, here's the key to your weak argument about 'stalking.'
Zimmerman's behavior until he pulled that gun is known to have been 100 PERCENT LAWFUL. He was allowed to follow Trayvon Martin.
Yet you're condemning him for something he had a legal right to do.
When he pulled the gun . . . was it lawful? It depends on whether he was in fear for his life. I don't think anybody except George Zimmerman will ever know for sure. But two black eyes, a broken nose, several lacerations on the back of his head, and a neck injury suggests that he probably WAS.
Do you suppose Martin had any significant injuries besides the bullet wound? If he didn't, then the aggressor in the actual assault becomes quite clear.