That is incorrect, and I respectfully disagree. You're half-way there. Hate speech is protected speech. Incitement of violence is completely different from hate speech, and it is absolutely illegal. Consider the following scenarios:

1) Standing up and saying "I hate black people. I wish they would all die." 2) Standing up and saying: "I hate black people, if you see them, kill them."

There's a clear difference here. The first is speech, an opinion, not directing action, advocating for violence, or to break a law. I say that's protected, as distasteful as it may be. The second is clearly criminal, and illegal. It is speech, but it is directing violence, and a law to be broken. That is the incitement of violence and a crime.