While the people directly responsible for this atrocity are those who did it, the US press bears a heavy indirect responsibility in my view. They stirred up racial antagonism with their outrageous and incessant coverage (four weeks straight) with everything viewed through a racial context of the Martin verdict (interesting how they utterly ignore the weekly weekend slayings of young people in Chicago; at “best” their coverage is limited to how many “routine” shootings occurred, the victims’ are generally nameless). I doubt those in journalism feel he slightest shame for what they have reaped in America; they are probably smug that they did it.
Actually it's the whole liberal edifice that's responsible. If criminal black youths had been cracked down on going back fifty years ago, we wouldn't have the problems we now have. Things changed a bit for the better when they made the decision to keep violent offenders in prison longer about 20-30 years ago, but there's still a very large segment of black youths who are basically feral. Until they're shown, by very harsh methods since gentle persuasion doesn't do much of anything, the error of their ways, cities are going to have these incidents. Which seem to have increased exponentially since 2008.