Free Speech - Not So Sure?

Where does the line blur between free speech and hate speech? We sit on the verge of revolution just as our country did 200+ years ago. What is allowed to be spoken? Is intent and provocative statement in and of itself enough to cause action, and with that action do we break the law?  

http://www.uscourts.gov/about-federal-courts/educational-resources/about-educational-outreach/activity-resources/what-does