Not if he has a gun. That's the messed up thing about stand your ground states. Someone could theoretically pull a stunt like this, and pull a gun once they're getting beat up. The Trayvon case showed that you can antagonize a person, and once they start fighting you if you end up in a situation where you could make a claim that you "feared for your life" and you can show signs of a fight you can kill them.
Theoretically an armed person could walk up to someone, slap or spit in their face, berate them, do anything to them, and as long as they are getting the worse of an altercation they could pull their gun out and kill someone.
Predation runs rampant in impoverished areas, and poverty is actually the natural state of humanity. Nearly every culture on earth has been poor ever since modern man has existed except when capitalism was invented, but capitalism doesn't eliminate predatory behavior altogether. Capitalism lessens physical predation because it can create jobs for a large group of people, but it shifts physical predation to economic predation, just not on an extremely cruel level, like we don't have debtor's prisons and shit anymore, and all poor people don't just starve to death, but there is still huge wealth inequality.
American ghettoes are impoverished which leads to predation via drug dealers and gangbangers, which intimidates and shapes the rest of the people in those areas. Combine that with a lack of father figures and a lack of education and you end up with a lot of people who only know how to solve confrontations or anything they perceive as disrespect with violence. Black identity in America is also complicated because most of the black American experience has involved managing and reacting to violence. Add to that the stereotypical macho portrayal of the black male and you end up with a lot of people who feel like the default power image of a man is a no nonsense guy like Tupac, or a random thug. Put it like this, Anderson Silva is tough and probably grew up poor, but I doubt if his first instinct would be to punch that nerdy guy and beat him to the ground, nor would he feel like less of a man for not doing it.
This is why I think every male (regardless of race) should be taught wrestling and something like jiu jitsu from grade 1 to grade 12. Insecurity causes a lot of dudes to poke their chest out just as much as it causes some men to fear confrontation.
But think about that. What is it actually a challenge to? What are the words challenging?
Bill Gates is nearly the richest man in the world, but if you asked him "you got a problem?" you think he'd feel comepelled to fight? Intellect always trumps individual strength because the smarter person/people will always be in control at the highest level regardless of physical strength. Fighting outside of self defense is stupid and doesn't lead to anything good.