The line must be drawn somewhere, we don't hold everyone responsible for every action they take.

I'd compare "inciting violence" to a woman dressing in provocative clothing in a bad area of town late at night. Very few people would blame the woman and say she's legally responsible if she's attacked, I hold the same line on speech.

Say what you want, dress how you want, it doesn't matter. If another person actually causes harm they can't shirk the blame off on you, they made the choice to commit violence.