When is protesting going to be defined in a different manner?

The First Amendment was designed to protect speech with which everyone agrees. It was designed to protect that which is disagreeable, repugnant even. That one voice, the one that everyone hates or laughs at, may be the only one that we need to hear. The problem in Charlottesville wasn't speech or a demonstration, it was in the police being ordered to back off and allow opposing sides to have at one another. The American Nazis (all ten of them) have frequently demonstrated over the decades. So have KKK members and white supremacists. And opponents have counter demonstrated. The difference was that police were told to stand down. That led to violence...

Some very good responses here. The way I see it, "protesting" is voicing your opinion. Once you start blocking roads/buildings, causing damage, or inciting/carrying out violence, though, then it becomes "rioting".

You can protest all you want on your own property. Once you get into the public domain, such as public parks, in front of buildings, etc. then you run into the need for permits.
Your right to protest cannot and does not allow you to infringe on or prevent other peoples' rights.
In NC there is legislation in the system that will (civilly) hold harmless drivers who hit protesters who are in the roadway. In general, pedestrians are not allowed on highways. Blocking traffic is illegal. If a government was so inclined, they could rightfully charge protesters with the federal crime of interfering with interstate commerce, as trucks that deliver goods are vital parts of the interstate commerce.

Most of all, attempting to influence a populace or government by force, threat of force, or kidnapping, is DOMESTIC TERRORISM and should be punished as such.
Domestic Terrorism:
"activities that (A) involve acts dangerous to human life that are a violation of the criminal laws of the U.S. or of any state; (B) appear to be intended (i) to intimidate or coerce a civilian population; (ii) to influence the policy of a government by intimidation or coercion; or (iii) to affect the conduct of a government by mass destruction, assassination, or kidnapping; and (C) occur primarily within the territorial jurisdiction of the U.S."

https://en.wikipedia.org/wiki/Domestic_terrorism