Anyone who has considered child porn speech is smoking something. We have agreed the act of taking pictures or videos of children in those situations to be illegal, it isn't about the meaning or speech a person may apply to that final product.

Slander and death threats are harder to define. You have to show an active plot to commit the crime, not just a statement. At that point the plot, the action you took, is the crime rather than your words.

Porn is not speech.

Pornography is properly regarded as a form of speech

Free speech is protected by cases over porn where the government lost - its one of the strongest tests of speech.

Porn is 100% speech.

The concept of free speech predates the US constitution or even its government.