It seems every few months for the past few decades we witness fresh protests to push a prosecutor to indict the killer of a black man especially if that killer is white.

In fact, these protests have become commonplace, even expected, as if protesters are stock characters in a national theatrical classic, revived in cities across the country every year.

When Michael Brown was shot by Ferguson police officer Darren Wilson on August 9, it looked like Ferguson, Missouri, was going to serve as just one more stop on the national tour of this classic drama. But it didn’t.

We have seen the officer, security guard or vigilante assailant  protected from arrest and whisked out of the reach of the angry black people. We have seen indictments await grand jury approval. We have seen prosecutors bungle trials.